In food writing, there is a specific sub-genre for works (both short and long) that are photo-heavy, with particularly good-quality photos.
Where you draw the line depends on your audience. An awful lot of people will buy a book or read a blog about food just for the pictures. There's even an entire subset of videos that show recipes with only the barest words shown on the screen (the ingredients, the amounts (if you're lucky), and some directions (maybe)). They're all flashy, gooey, creamy, rich, and take a lot more work and skill than is implied (most of the work is shown in fast forward or time skips).
These are food porn with no redeeming qualities. Because none of the recipes are practical to make and they don't teach any skills. I'm sure some people make them, but I'd guess over 99% of the viewers who say they'll make them, or think about making them, never do.
Then there is food writing that is actually useful. Restaurant reviews that give some history or understanding of the cuisine. Recipes that people can and will make. Information about food history, cooking technique, etc.
What's the difference between porn and erotica? Is the focus the "money shot" or the information? In fiction, erotica means there's a story there. In food writing, it's about whether you are conveying shallow emotional impact and not much else vs solid information coupled with the wow factor.
Most of these works have some pictures. Only older books have none or just a couple (because it used to be expensive to include pictures in books, even line drawings, and color plates, very pricey). How many you include depends on your budget (printing them costs more if in color, though not too bad, but getting professional photography is expensive if you don't do it yourself), your medium (if a blog, photos are key), and your readership.
Then there are hardcore informational food books. Usually there aren't a lot of pictures in these, though there are exceptions.
You didn't ask about the type of pictures, but I think this is an essential part of answering your question. There are pictures to draw in the reader and pictures to show something specific. And a lot of overlap.
You want something that shows the finished product (sometimes whole, sometimes sliced into). With a blog this is completely essential, with a cookbook, you can show a percentage of them. If you put in a lot of pictures at different angles, you cross the line into food porn (which is fine if that's what you're after).
Showing photos of different steps in a recipe is nice on a blog and useful for people who aren't very skilled at cooking, or for steps that are unusual. You can't always explain things verbally. Sometimes you need to show. But even blogs that show every step can get to be a bit much, though I'm very fond of this blog, I honestly can't read too many like that (it's just done exceptionally well). Though in a way it's like watching a video you can skim and move your eyes around, which is nice.
My suggestion for the level you seem to be going for (actual useful information for home cooks) is to take out all the pictures, drawings, graphs, whatever. Then read the section (and send to beta readers) and see if it makes sense. Once it does, then add back a few pictures. Focus on one overall shot and then pictures that show something that might be confusing to some readers in text alone. If you have the space, add more for visual appeal and to increase the information value.
Make the text the star.
But use pictures as much as you can without overwhelming the text. When you have space considerations, let the text have first dibs. Then fill in the space as you wish with high quality photographs or other images.