
So, after a recent Costco trip, I ended up with a whole bunch of meat – Tri-tip, to be exact. You know how it is at Costco – you buy a lot, and that’s exactly what I did with the Tri-tip. I was in the mood for something Mexican, so I decided to make some delicious Tri-tip Fajitas.
I usually use skirt steak, flank steak, or chicken when making Fajitas but I figured why not give Tri-Tip a shot. As long as you cook the meat so it’s tender it should turn out great!

What is Tri-Tip
Tri-Tip is a triangular-shaped piece of beef found at the bottom of the sirloin region of the cow. It’s lean but has just enough fat to keep it juicy and flavorful during cooking. This cut of meat became popular in California during the 1950s and is now a favorite across the US and a few other countries.

When selecting the peppers to use for this fajita recipe you can use whatever you want. Green Bell Peppers sometimes don’t agree with me so this time around I decided to use red, yellow and orange peppers. Feel free to use whatever you prefer.
Recipe Tips
- When the time comes to warm up your tortillas, you have a few options. You can wrap the tortillas in foil and bake them for 10 minutes at 350°F. You can also put them in a non-stick pan to heat both sides of the tortilla (this is how I usually do it), heat them over an open flame, or if you must, wrap them in a damp paper towel and microwave them for about 30 seconds.
You also have a few options when it comes time to cook the tri-tip. For this recipe, I seared the meat for a few minutes on each side in a cast-iron pan then put it in the oven until it was done. You can also use my Baked Tri-Tip, Smoked Tri-Tip, or my Grilled Tri-Tip recipes.

Gather your Ingredients
You will need the following ingredients to make this Tri-Tip Fajitas recipe. For ingredient amounts please refer to the printable recipe card at the bottom of this post.
- Tri-Tip – make sure you remove any excess fat, especially the hard stuff
- Extra Virgin Olive Oil – try to use the best quality olive oil that you can
- Beef Seasoning – alternatively you can use some salt, pepper and garlic powder. Or even better you can use my Santa Maria Tri-Tip Seasoning
- Red Onion – if your knife skills aren’t up to par, use a mandolin to slice the onion
- Orange, Red & Yellow Bell Peppers – or use any color combination of peppers you want
- Flour Tortillas – Burrito-size tortillas are perfect for this fajita recipe
How to Make Tri-Tip Fajitas
- Preheat the oven to 375°F. Place the cast-iron pan on the stove and heat until it’s nice and hot.
- Meanwhile, season the tri-tip with 2 beef seasoning. Let sit at room temperature while the oven and skillet heats up.
- Place the seasoned tri-tip in the pan and grill for 5 minutes on each side until crisp.
- Place the cast-iron skillet in the oven for 10-12 minutes or until the internal temperature reaches approximately 135°F.
- Let the tri-tip rest for about 10 minutes then cut into thin strips.
- While the tri-tip is resting, heat another skillet over medium-high heat.
- Add the olive oil, peppers and onions. Toss them with a little salt & pepper. Stir occasionally for 6-10 minutes.
- Heat the tortillas using your preferred method.
- Add the beef and veggies to the warmed tortillas and garnish with your favorite toppings.
More Recipe Ideas
Printable Recipe Card

Tri-Tip Fajitas
↑ Click stars to rate
Ingredients
- 2 lbs Tri-Tip, trimmed of excess fat
- 1 Tbsp Extra Virgin Olive Oil
- 2 Tbsp Beef Seasoning, or more if needed
- ½ Red Onion, sliced
- 1 Orange Bell Pepper, sliced
- 1 Red Bell Pepper, sliced
- 1 Yellow Bell Pepper, sliced
- 8 Flour Tortillas
Instructions
- Preheat the oven to 375°F. Place the cast-iron pan on the stove and heat until it’s nice and hot.
- Meanwhile, season the tri-tip with 2 beef seasoning. Let sit at room temperature while the oven and skillet heats up.
- Place the seasoned tri-tip in the pan and grill for 5 minutes on each side until crisp.
- Place the cast-iron skillet in the oven for 10-12 minutes or until the internal temperature reaches approximately 135°F.
- Let the tri-tip rest for about 10 minutes then cut into thin strips.
- While the tri-tip is resting, heat another skillet over medium-high heat.
- Add the olive oil, peppers and onions. Toss them with a little salt & pepper. Stir occasionally for 6-10 minutes.
- Heat the tortillas using your preferred method.
- Add the beef and veggies to the warmed tortillas and garnish with your favorite toppings.