Oh cool, 8ch doesn't delete all the keto threads. Congrats on avoiding the rampant vegan faggotry and corporate product shilling that 4chan has embraced. I hereby formally renounce, denounce, and give up on that other trainwreck and migrate here.
OP, consider the basic English cauliflower-cheese. You make a cheese sauce, dump it over a bunch of parboiled cauliflower, and throw it in the oven for 20-30 minutes.
I start by rinsing, cleaning, and cutting up the florets of the cauliflower (I use two entire heads of it, enough for three meals), then dumping it into salted boiling water, then draining it and putting it into a glass oven dish. Drain it THOROUGHLY because you don't want a lot of water diluting and ruining your sauce.
I'm a lazy bastard so my cheese sauce consists of as little heavy cream as is necessary to cover the bottom of a saucepan, followed by crumbling in about 300g of high-quality aged sharp cheddar cheese. Keep stirring and eventually the cheese will dissolve into the cream. Then, depending on how liquid the result is, I dump some cornstarch in as thickener. Yes, I know cornstarch isn't "keto", so what, you're allowed 20 grams of carbs per day, use some of them. It doesn't take much. Heat and keep stirring until it thickens.
Be really careful not to overheat the sauce while making it, because if you do, the proteins in the cheese will denature and glob together and you'll end up with a sort of cheese grit in yellowed water. Still tastes ok on the cauliflower but not nearly as good.
DRAIN that cauliflower one last time (put a plate over your baking dish, or use a wire splatter-screen, or whatever, to keep the cauliflower from falling out). I cannot sufficiently emphasize the need to drain thoroughly. You might even try pre-baking the cauliflower to dehydrate it a bit – hmm, maybe I'll try that tonight.
Now pour the sauce all over it. Use a silicone spatula to scrape the sauce out of the saucepan. Leave a little to eat while everything else bakes, see picrelated, he is my spirit animal when it comes to what's left in the saucepan.
At this point I like to sprinkle paprika all over the top. The Bongistanis traditionally use mustard powder mixed into the sauce instead, but I don't like the taste. (I'd prefer some other pepper powder instead, say something that actually adds some spiciness, but where I live, the selection of Western spices is seriously fucking limited because Chinese inbreedingness.)
Then bake at around 180C for 20 minutes while you broil a steak or fry some salmon or whatever.
Whatever you don't eat at this meal, you can refrigerate and reheat for the next one. I usually break the above into three days of meals (I'm only eating one per day to try to break the weightloss plateau I've been stuck on forfuckingever).
Net is about 500 calories and 25g protein from the sauce, 50 calories and 6g of carbs and 4g of protein from the cauliflower (2/3 of a head, I'm assuming 200g weight for that), and a few grams of carbs from the cornstarch if you use it.