Heat a large, deep skillet over medium heat. Add the olive oil, butter, chopped onion, garlic, green pepper and jalapeño. Cook for 3-5 minutes, being careful not to burn.
Add the entire can of tomatoes, rice, chicken stock, black beans, taco seasoning, pepper and salt (if using). Stir to combine.
Bring mixture to a boil, cover and reduce heat to low. Cook for 20-25 minutes or until rice is tender and most of the liquid is absorbed.
Stir in cilantro.
Notes
Plain long-grain rice may be substituted. To make vegan: eliminate butter and use 3 tbs olive oil. Substitute vegetable stock for chicken stock.