I make a mean pot of chili, using just beef, beans, onions, garlic, and spices (LOTS of spices!), but want to make a vegetarian version. I know next to nothing about the various types of meat substitutes. Can you recommend something that would approximate the texture of ground beef - or even better, if possible, cubed beef? I'm not overly concerned about flavor since, as I said, I'll be adding plenty of spice, but I'd like something with a convincing texture.