Start with their naive goal
A character wants something. An antagonist is preventing it. This dynamic IS the story, over and over.
We generally don't get the character's 'want' spelled out in bold type. At the start they usually have a naive idea of their goal. This naive goal is easier to ret-con after you know what the bigger conflict is about.
As an example, the Character is about a smalltown girl who wants to go to Hollywood to be a movie star, and the Theme will be whether (or how much) she will compromise her values to achieve fame. This Thematic conflict isn't apparent at the start of her journey, so we give her a naive goal instead: she wants to be 'just like Lana Turner'. In her mind that means being a movie star, but she doesn't really understand how to get there.
Of course the reader knows she can't literally become Lana Turner. It's not a bait-and-switch goal, rather we see instantly that this girl's desire is a) not that realistic, and b) kinda immature.
We also know (outside the story) that this is a goal lots of girls have but can't/won't do anything about, so she isn't even special. This 'inertia' and the doubters in her life are her first antagonist – the thing preventing her from becoming Lana Turner.
The combined conflicts and resolutions create the Theme
She needs to overcome this first obstacle, the first step that sets her apart from the wannabes. Let's say she tries to convince the doubters but they dismiss her actress dreams, so the only alternative is to get around the smalltown inertia. Somehow (perhaps a small moral compromise for ticket fare) she hops a bus to California and the adventure begins. She has defeated her first antagonist with many more to come.
As author you need to 'dramatize' each conflict according to character and theme. How does this conflict make her behave? Is she resourceful? Bull-headed? If the theme is about compromising for fame she will be buying into this theme from the start. Each conflict is overcome (somehow) according to the theme's premise.
Stories are about conflict.
All of my attempts at writing devolve into overthinking plot,
characters, and motivations...
Perhaps "overthinking" is not the right term and I'm simply a
pea-brained dum-dum who gets overwhelmed at the slightest hint of
struggle
Very quickly, she's been confronted with her first roadblock (if a bit abstract) and overcomes it. The story has begun.
When the character figures a way around all her antagonists, or she loses the want, the story ends.
You don't need to struggle, but your characters do. She has a vague goal in mind, and in trying to align herself with that goal she is coming across new obstacles, new antagonists preventing the goal.
With each step she is 'leveling up', getting closer to her goal and becoming less naive. There might be enough story/conflict just trying to get to Hollywood. Most of us start with naive dreams that got derailed by life, but we're rooting for her now because she won the first battle. How far can this contender go?
Without a conflict/antagonist there is no character dynamic, no story. Antagonists can be abstract, conflicts can be small, but without them characters are just people who exist. There is no fuel to keep the story going.
Characters get a naive goal at the start. It doesn't matter if they 'earn' that goal by the end, but it will be recognized as naive by the end (assuming it's remembered at all).
If you know the Theme and Character, you can plot anything
I just can't bring myself to write something half-baked.
How refreshing!
But to go with your analogy, there needs to be ingredient prep for something to not be half-baked.
That takes me back to the planning board. What does this character
want? Why? That leads to philosophical questions I'm not nearly
equipped to answer...
It's not that I need to add conflict—I know that—but that I don't know
what the conflict ought to be.
Neil Gaiman, in his course on writing, says (and I paraphrase),
"You've got an idea for a story. Now you've got to figure out what
it's about." In a nutshell, that's my problem. Trying to solve that
mystery ends up with me lost in a forest at night
M'kay. I'm going to poke a hole in this analogy. No one (except maybe Bambi) 'wakes up lost in a forest at night'.
They walked willingly into the dark forest, step by step, because they had a naive goal that brought them there. Maybe the forest is bigger than thought, or the day was wasted and now comes the night, but there was a setup that got that character here. The pay-off is a new conflict.
This 'forest at night' is an antagonist. What does it have to do with the goal of being Lana Turner...? It doesn't. But her goal (and moral compromises, if that's the Theme) led her here, so now what?
Go back to the Character, how do they behave with this latest antagonist?
Go back to the Theme, how does this conflict get 'resolved'?
There are writing tricks to keep this setup and pay-off going. 'Resolving' a conflict doesn't mean it was solved, it just means the conflict concludes and the story moves to a new conflict.
Scene-Sequel, No-And/Yes-But, out of the frying pan into the fire, Accept/Deflect/Reject (attack/parry/block).... Plots can always keep going, but characters and themes can be stretched past credibility.
There are story structures innate to certain themes. In Comedy it's an escalation of the ridiculous, in Horror its diminishing resources and isolation, in tragedy it is hubris leading to a fall, Adventure relies on coincidences and seat-of-the-pants escapes....
Endings don't really matter – you can tack a happy ending on a horror story and it's still a horror story. Specific plot points probably only matter a little, but how all the conflicts are resolved along the way accumulates into the Theme.
In other words, because the journey would be what's important, not the
destination.
The 'journey' is the full-realization of Character and Theme. The 'destination' is the story's ending. So, yes, journey is more important than destination but it's not some aimless walkabout until it all falls into place.
But isn't 'Theme' just some mystical mumbojumbo that springs naturally and unattended without any guidance, like weeds and serial killers?
However, without a sense of direction, the words I type feel like
fodder, or lard or filler or whatever you want to call it. So, here's
my question: can one write an unambitious story without it feeling
like a waste?
I hear you. I'm not a fan of pantsing the theme.
Stephen King's stories go nowhere, he just sets up a cast with interpersonal problems and interrupts them with a monster. There's no meaning or realization. No one grows. There's no purpose or reason for the menace. He makes bank and has fans, and wrote 700-page novels on cocaine. He is a publisher's dream. I personally can't get through his books, they all feel the same. Same characters, same conflicts.
And no theme. It might as well be D&D to me.
I use to 'discovery' write, but it was meandering and repetitive. It had setups without pay-offs, and empty characters that were there to be stooges and villains for my Mary Sue over-powered anti-superheroes. I had nice language skills (privilege of education and geologic location I suppose), but the plots were silly and lacked depth. I tacked them out on generic 3 act structure, which forced certain plot beats and I felt it had improved, but then I did it again with another project and it became the same story. lol – not sure why I thought a formula would preserve what's unique about my stories, it's literally a formula.
The real problem was no theme, so I couldn't finish them. They were just words, and plot beats, and action stuff that happened (maybe I lacked the cocaine budget to stay motivated).
For people who discovery-write (and the fans who read them): cool. It's not for me. I recognize it when I see it, it does seem to enable more finished/published works, but I think there's a lot more pushback than acknowledged when plots go off the rails breaking their own premise, and lead characters are sidelined by manipulative plot-twist hi-jinks. It all feels like Shaggy Dog stories to me.
Theme and Character drive the conflict (which is the story)
You don't need to know the ending (some stories can keep going forever), but if you know the Character then you know how they will act in a conflict and this should change over time as they become more experienced. Their arc will compliment the overall conflict.
If you know your Theme you know how each conflict should be resolved – not specifically in a plot-way, but you know what kind of story mechanism resolves the conflicts: perseverance and bravery, guile and wits, self-sabotage and disaster, comedic surprises.
It's a lot easier to write when you understand the goal. I thought my old plots were great, but reading them later they didn't go anywhere. There were nice moments, but the tone was all over the place, and characters acted inconsistently to make the plots happen. Since I switched to Character and Theme as the main drivers I don't really have any problems writing. My plots didn't become less intricate, but they hold together better, with longer, better setups and pay-offs.
Imho Themes, like character arcs, build over the course of the story but it's essentially a 'worldview' or an in-world dynamic I'm trying to convey. When characters buck against the Theme, the Theme should impose corrections on them. When characters work within the Theme, the Theme should re-enforce them. Therefore, in a "Theme arc", the theme will be tested by characters who want to defeat the theme or prove it wrong, they will be the outsiders in their own story, effectively the Theme itself is the final antagonist that's been there all along.... When they've finally resolved the theme, accepting, deflecting, or rejecting it, they have conquered this world.
What happens to smalltown girl who wants to be Lana Turner? Does she make it as an actress? Does she meet the real Lana? Does she have a final confrontation where her fandom is somehow useful...? idk, that's all plot, just another setup and pay-off. It doesn't tell me who she becomes as a Character and it doesn't inform me about how she resolves my Theme. Working the other way however, knowing the character's arc and theme, the plot (almost) writes itself. Story beats aren't about arbitrary time-ratios, they are the natural and deliberate moments where character collides with theme.