Skip to Content

Costco Sliced Sirloin Steak Quesadillas

Have you seen the Cuisine Solutions Sliced Grass Fed Beef Sirloin at Costco? It’s an awesome pre-cooked protein source for a minimal effort girl dinner or worked into other recipes. One of my favorite ways to use it is in simple steak quesadillas.

I pair the sliced sirloin with a few other Costco finds like low carb tortillas, Mexican cheese, and a creamy jalapeño dip made from nonfat Greek yogurt. Get your shopping list ready, and I’ll walk you through the recipe and all the specifics below.

sliced steak quesadillas on a cutting board with a sheet pan of whole quesadillas and lime wedges

Ingredients for Beef Sirloin Quesadillas

You’ll only need five core ingredients and a few additions like oil and spices. Here’s the full list:

  • Sliced Grass Fed Beef Sirloin – This has 19 grams of protein, 5 grams of fat, and 120 calories per 3 oz serving in case you’re looking for a substitute. Try my flank steak or shredded beef roast for homemade alternatives.
  • Peppers and Onions – These are both optional and customizable. You could bulk up your quesadillas with some roasted corn, zucchini strips, and a bit of spinach.
  • Shredded Mexican Cheese – I typically advise against using pre-shredded cheese, but the Mexican cheese blend from Costco melts perfectly fine for quesadillas.
  • Mission Carb Balance Tortillas – I was happy to see these turn up in Costco. I’ve been using them to make quesadillas for years now.
  • Olive Oil and Your Choice of Seasoning for the Veggies – A bit of salt helps with veggies release moisture and soften faster. Why not add a bit more kick with some chili powder and granulated garlic while you’re at it?
cuisine solutions sliced sirloin with sliced onions and peppers, Mexican cheese, and Mission carb balance tortillas

The packaging on the grass fed sliced sirloin says you can serve the beef chilled and to only reheat for 30-60 seconds at most to avoid over cooking it. I find the beef will continue cooking once it’s in the quesadillas, but I still like to toss it with the veggies (off the heat) to pick up any remaining fond and flavor from the pan.

cooked peppers and onions in a skillet with sliced sirloin

If you wanted to make your own sliced steak at home, try using pairing this best steak marinade with top sirloin and grilling or pan searing.

Being a Kinda Healthy recipe, I’ve kept the cheese to a minimum. But if you have the calories to spare, an extra 1/2 ounce of cheese per tortilla really hits the spot!

If you need an extra protein boost, you might try the Counter protein tortillas I used to make my chicken snack wraps.

tortillas on a griddle topped with shredded cheese, steak, peppers, and onion

Quesadillas in Action (Video)

If you’re a visual learner, check out the video below where you can see me make these quesadillas along with nine other meals with high protein Costco finds. You may also want to check out my complete high protein Costco shopping list if you’re looking to expand your options.

What to Serve with Steak Quesadillas

In the photos, you’ll see salsa verde, pico de gallo, and my spicy ranch Greek yogurt dip. A classic hot sauce or something like my creamy avocado salsa would also be great pairings.

For side dishes, check out this Mexican cauliflower rice, charro beans, or my 10-minute refried black beans.

However you end up serving your sirloin quesadillas, I’d love to hear your thoughts about the recipe. Let me know in the comments or in a recipe review!

sliced steak quesadillas on a plate with creamy jalapeño dip, pico de gallo, and salsa verde on the side

Sliced Sirloin Steak Quesadillas

Yield: 8 Quesadillas
Prep Time: 10 minutes
Cook Time: 20 minutes
Total Time: 30 minutes

High protein quesadillas with lean sliced sirloin, low carb tortillas, peppers and onions, and a Mexican cheese blend.


  • 1/2 package (about 1 pound) Costco Cuisine Solutions Sliced Sirloin
  • 2 Poblano or Green Bell Peppers
  • 1 medium Yellow Onion
  • 1 1/2 Tablespoons (24g) Olive Oil
  • Pinch of Fajita or Taco Seasoning (or simply salt and pepper)
  • 8 Mission Carb Balance Tortillas
  • 8 oz Shredded Mexican Cheese Blend


  1. Slice the onion and peppers into thin strips and the steak into bite size pieces. Set aside.
  2. Heat a large skillet over medium-high heat with the olive oil. Once hot, add the veggies and season with fajita seasoning, taco seasoning, or a pinch of salt and pepper. Cook for 8-10 minutes, stirring occasionally, until the veggies soften and begin to pick up a bit of color.
  3. Once the veggies are finished, turn off the heat and add the steak. Toss everything together and set aside.
  4. Spray a large griddle or skillet with a bit of cooking spray or a drizzle of oil before adding the tortillas (low to medium heat). Cover the top of each tortilla with an ounce of cheese. Once the cheese begins to melt, add about 2 1/2 ounces of the steak and veggies to one side of each tortilla. Fold the other side over and gently press to seal.
  5. Cook for another 1-2 minutes per side until golden brown.
  6. Slice and serve warm with your choice of dips or salsas.
Nutrition Information:
Yield: 8 Serving Size: 1 quesadilla
Amount Per Serving: Calories: 295Total Fat: 18gCarbohydrates: 23gFiber: 16gProtein: 25g

Want more kinda healthy recipes?

Follow me on Pinterest to see all of my recipes organized in one place with photos!

Skip to Recipe