Homemade Slow Cooker Vegan Chili

Heat oil in a large skillet over medium heat; stir in bell peppers and onions. Cook and stir until the onion has softened and turned translucent, about 5 minutes. Add garlic and cook until fragrant, 1 to 2 minutes. Transfer to a slow cooker.

Add zucchini, yellow squash, and spinach to the slow cooker; stir to combine. Mix in diced tomatoes, corn, black beans, kidney beans, garbanzo beans, tomato paste, vegetable broth, chili powder, oregano, and cumin. Season with salt and pepper.

Cook on Low for 4 to 5 hours.