Blackstone Steak Fajitas Recipe – Easy Tex-Mex on the Griddle

If you love sizzling steak fajitas with bold Tex-Mex flavor and crave that perfect caramelized char you can only get on a flat-top grill, this recipe’s for you. We took inspiration from a mouthwatering meal at La Casona Tex Mex in Lake Jackson, Texas—juicy steak, caramelized onions and peppers, sizzling mushrooms, and just the right kick from fresh jalapeños. The whole dish was saucy, smoky, and bursting with flavor.

Naturally, I had to try making them myself. So I recreated them right at our RV site using our Blackstone Adventure Ready Griddle—and the results? Incredible.

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The Setup

Cooking fajitas on a Blackstone griddle is a game-changer. That flat-top surface gives you:

• High, even heat across the board
• Tons of room to cook steak and veggies side-by-side
• Easy caramelization without overcrowding the pan

Whether you’re hooked up at a site or boondocking in the middle of nowhere, the Blackstone brings restaurant-quality cooking to your campsite.

Sizzling Steak Fajitas – La Casona Tex-Mex Style

Prep Time: 20 minutes
Cook Time: 20 minutes
Total Time: 40 minutes
Servings: 4

Ingredients

For the Fajitas:

• 1.5 lbs flank or skirt steak, sliced against the grain
• 1 red bell pepper, sliced
• 1 green bell pepper, sliced
• 1 yellow onion, sliced
• 1 cup baby bella (cremini) mushrooms, sliced
• 1–2 jalapeños, sliced (remove seeds for less heat)
• 1 tbsp olive oil
• 1 tbsp butter

For the Marinade:

• 3 tbsp soy sauce
• 2 tbsp lime juice (fresh is best!)
• 2 tbsp olive oil
• 2 tsp brown sugar
• 3 garlic cloves, minced
• 1 tsp cumin
• 1 tsp smoked paprika
• ½ tsp chili powder
• ½ tsp black pepper
• ¼ tsp salt

Optional Toppings:

• Warm flour tortillas
• Sour cream
• Guacamole
• Pico de gallo
• Shredded cheese
• Fresh cilantro

Instructions

1. Marinate the Steak

Combine all marinade ingredients in a bowl or zip-top bag. Add sliced steak and marinate and marinate for at least 1 hour or overnight in the fridge for maximum flavor and tenderness. Optional but recommended: Make a second batch of the marinade and set it aside to use while cooking for added sauciness.

2. Preheat Your Griddle

Heat both burners on medium-high. Add a splash of olive oil.

3. Cook the Steak

Sear steak in batches, 2–3 minutes per side, until browned and slightly crisp on the edges. Remove from griddle and cover loosely.

4. Cook the Veggies

Add butter to the griddle. Toss on onions and bell peppers. Cook 5–7 minutes until they start to caramelize. Add mushrooms and jalapeños, and cook another 3–4 minutes until golden and tender.

5. Bring It All Together

Return the steak to the griddle, mix with the veggies, and pour some of the reserved marinade over everything. Let it all cook together another 1–2 minutes, allowing the sauce to reduce slightly and glaze the meat and vegetables. Squeeze a little lime over the top before serving.

6. Serve Hot

Load into tortillas and add your favorite toppings. Eat immediately while it’s still sizzling!

RV Galley Tips

• Use a Blackstone spatula kit to handle meat and veggies with ease
• Store pre-sliced veggies and steak in stackable containers to save fridge space
• Clean your griddle while it’s still warm to make cleanup a breeze

Recipe Notes

• Marinate Overnight: For the best flavor, marinate the steak overnight. It tenderizes the meat and infuses every bite with bold Tex-Mex seasoning.
• Use Reserved Marinade: Making a second batch of marinade to pour over the fajitas while cooking adds a rich, saucy finish — highly recommended!
• Griddle Tip: Preheat your Blackstone for 5–10 minutes before cooking. A hot surface is key to getting that caramelized sear.
• Veggie Flexibility: Don’t have mushrooms or jalapeños? You can swap in zucchini, poblano peppers, or even corn for a twist.
• Tortilla Tip: Warm your tortillas on the griddle’s edge for a soft, slightly crisp finish right before serving.
• Spice Level: Adjust the heat by using more or fewer jalapeños — or leave the seeds in for extra kick.

Final Thoughts

These Blackstone fajitas were every bit as good as the ones we had at La Casona—maybe even better since they were made right at our RV site, fresh off the griddle. The marinade brings just the right balance of smoky, tangy, and sweet, while the baby bellas soak up all that steak juice like little flavor bombs.

Adding a little extra reserved marinade to the griddle as everything cooked created a light, flavorful sauce that really took things up a notch.

If you’re traveling with a griddle and want a meal that impresses without being complicated, this one needs to be on your list.

Let me know if you make it!

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