You sure can. I simply love recipes that are easily adaptable to different dietary needs. To make this chili vegetarian chili, you can simply omit the ground beef. You can used tofu instead or because the other flavors and texture in this chili are so great, you leave it out altogether. If you want to make this a vegan recipe, you'll also want to substitute the chicken stock with vegetable stock and the Worcestershire sauce for liquid aminos.