Seed, slice,, and prepare the onions, peppers, and garlic.
Heat olive oil in a large pot over medium heat. Once hot, add onions and garlic and cook, stirring occasionally, until onions are translucent, about 5 minutes. Add peppers, jalapeno, and tempeh and cook until tempeh is browned, 5-7 more minutes.
Stir in the remaining ingredients. Reduce heat to a low simmer and cover. Cook chili for 20 more minutes, stirring occasionally, unti thick and bold flavored. Remove from heat. Taste and adjust seaonings.
Serve immediately with green onions, jalapeno, and avocado.