In a saucepan, heat oil over medium heat. Cook onion until soft. Add garlic and thyme, and cook for an additional minute. Remove and place in the crock pot bowl.
In the same saucepan, brown the ground beef. Drain fat if desired. Place beef in a crock pot bowl with onions.
Add to the crockpot the tomatoes, broth, peppers, water, and sauce. Stir to combine. Cook on low for 4-6 hours.
Add rice. Stir to combine. Cook an additional 30 minutes. (Or just add rice 30 minutes before serving)
Season with salt and pepper to your liking. Enjoy while warm. If saving for later, I would cook the rice and keep separate and add when ready to serve.
Notes
use tomato juice for more liquid in your soup if you cook with rice
try different flavors of diced tomatoes like fire roasted, Italian style, or chili ready tomatoes
works great with brown rice and chicken broth too
add Italian seasoning instead of just thyme if you like that
use a pressure cooker to keep this a one pot meal
leave out rice to keep it low carb or keto
add cheese to make it richer
add more or less rice to make it thicker or thinner