Slow Cooker Steak Fajitas Recipe for Tender, Flavorful Meals

Slow cooker steak fajitas is an easy, flavorful recipe made with just a few ingredients: beef, onions, bell peppers, diced tomatoes (or salsa), and fajita seasoning. It fills the kitchen with aroma while cooking and quickly becomes a family favorite. Instructions for making these steak fajitas in an Instant Pot are included as well.

Ingredients For Slow Cooker Steak Fajitas

• Beef — sirloin, flank, skirt, or another preferred cut, sliced into thin strips (about 2 pounds)
• Fajita seasoning — store-bought or homemade (recipe below)
• Bell peppers — 2 large, sliced (use a mix of colors if desired)
• Onion — 1 large, sliced
• Diced tomatoes with juices or salsa — one 15-ounce can

How To Make Steak Fajitas In The Slow Cooker

Slow Cooker

1. Add the sliced beef, bell peppers, onion, diced tomatoes (or salsa), and fajita seasoning to the slow cooker. Stir to combine so the seasoning evenly coats the ingredients.
2. Cook on HIGH for 2–3 hours or LOW for 4–6 hours, until the beef is tender and the vegetables are soft. Taste and adjust seasoning if needed, then serve.

Instant Pot

1. Set the Instant Pot to Sauté and add 1 tablespoon oil. When hot, brown the beef in batches for 2–4 minutes until seared. Remove the beef and drain excess fat if needed.
2. Add the sliced onions and bell peppers and sauté for 3–5 minutes until slightly softened. Pour in 1/4 cup beef broth or water and deglaze the pot, scraping any browned bits from the bottom.
3. Return the beef to the pot, add diced tomatoes (or salsa) and fajita seasoning, and stir to combine.
4. Secure the lid, set the valve to sealing, and cook on High Pressure for 9 minutes. When finished, quick release the pressure, open the lid, stir, and serve.

FAQs & Tips

What Are Fajitas

Fajitas are a Tex‑Mex favorite of seasoned meat cooked with onions and bell peppers, usually served with tortillas. Using a slow cooker or Instant Pot changes the cooking method but retains the familiar, savory flavor.

What type of beef should you use?

Flank or sirloin are great choices, but you can use skirt steak, flat iron, chuck, rump, or even stew meat. The slow cooker and Instant Pot make tougher cuts tender, so choose what fits your budget and taste. You can also substitute chicken, pork, or turkey breast if preferred.

Can you use different vegetables?

The recipe calls for 2 bell peppers and 1 large onion. Use any pepper colors you like and any onion variety (red, yellow, or white). You can add mushrooms, zucchini, or sliced jalapeños for extra flavor.

How do you serve this?

Serve the fajitas in flour or corn tortillas, over rice, or wrapped in lettuce leaves for a low‑carb option. They also make a great filling for burritos or enchiladas. Top with cheese, guacamole, salsa, sour cream, or chopped cilantro.

How do you store leftovers?

Store leftovers in an airtight container in the refrigerator for up to 4 days. Reheat gently on the stove or in the microwave.

What size slow cooker did you use?

A 6‑quart slow cooker or a standard Instant Pot works well for this recipe.

Mexican Inspired Recipes

• Chicken Fajitas

• Enchilada Tri‑Tip

• Salsa

• Salsa Verde Beef

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