Tofu, seitan, synthesized pea or soy protein… where I live, you can get vegan nonfat skyr that tastes every bit as funky as real skyr, and although it does have a hollow, oaty aftertaste, you can counter it pretty easily by adding a fat (I tend to carefully temper melted vegan butter and just add that) or using it with something (like jam, oats, and wheat germ/flaxseed) or as a thickener/creamy/cultured element in a recipe