Matar or green peas are the main ingredient here. Pay some attention to what kind you use, since it will dominate the flavor of your curry. You don't want to use sweet peas or any kind that's sweetish, because the peas will dominate the flavor of your dish. In fact, the kind of peas this is made with in India are large and not that sweet at all. You can use sweet peas, but in that case be prepared for the curry to have strong notes of sweet in it. Frozen peas are fine, and those are what I usually use, but if you do, you'll be adding them later in the recipe than if you were using fresh, because the frozen peas don't have to cook as much. Paneer, as most of you know, is an Indian cheese. I have, for as long as this blog has been around since 2007, used tofu, preferably super firm or extra firm, to sub for it in most Indian dishes that call for paneer, like this Vegan Palak Paneer with Tofu. Paneer is not a cultured cheese--it's a cottage cheese--made by hanging split milk curds in cheesecloth the night before. It tastes mild, not cheesy at all, and remarkably like tofu, except milkier, of course. Since the job of the spongy paneer is to soak in the flavors of the curry or gravy, tofu makes a great stand-in since it has a very similar texture and it pulls in the sauce too. I often advise sauteing the tofu lightly, or baking or air-frying it, before adding it to curries. That's because tofu can crumble easily in the curry, and sauteing helps it hold. But for this curry I prefer not to do this because the oil and crust can keep the sauce from soaking in, and you really want them to for the best flavor. If you must, air-fry the tofu cubes without the oil so they develop a slight crust. Super firm tofu works best for this. If you have some of my tomato onion masala sauce for quick curries in the refrigerator, you can make this recipe almost without any more chopping and with a minimal amount of cooking. But blend the masala sauce first, because you want the gravy to be really smooth.