Heat oil in a large non-stick skillet over medium heat until hot.

Cook carne asada until browned evenly, pour off drippings

Add onion, tomato, salt and pepper

Bring to a boil

Reduce heat, over tightly and simmer 20 minutes or until steak is fork-tender

Remove steaks and keep warm

Stir beans into cooking liquid, bring to a boil

Reduce heat and cook 7-10 minutes or until sauce is thickened, stir frequently

Mix in spinach, remove from heat

Let stand 1 minute

Serve bean mixture with cooked carne asada