Step 1

Preheat the oven to 350°F. Using a pastry brush, brush 2 tablespoons of canola oil onto the inside bottom and sides of a 13x18-inch rimmed baking sheet tray. You will need a second rimmed sheet tray for the baking process. Set aside.

Step 2

In a large skillet, on medium-high heat, heat 1 tablespoon canola oil. Add the 2 cups chopped yellow onions and saute them for 2-3 minutes or until they are translucent and soft. Transfer the cooked onions to a plate and set them aside.

Step 3

To the same large skillet, on medium-high heat, add half of the ground beef and one of the 1 oz. packets of taco seasoning, 1 teaspoon salt and ½ teaspoon black pepper. Cook the ground beef for 4-5 minutes, breaking it up into crumbles until there is no longer any pink and the ground beef is completely coated with the taco seasoning. Transfer the cooked ground beef to a large bowl or large shallow dish, and repeat with the second half of the ground beef and the second 1 oz. packet of taco seasoning, remaining 1 teaspoon salt and ½ teaspoon black pepper until all the ground beef is cooked. Transfer the rest of the cooked ground beef to the bowl with the first batch of cooked ground beef.

Step 4

Add the cooked yellow onions to the cooked ground beef in the bowl, and stir to incorporate.

Step 5

To the prepared rimmed baking sheet tray, you will lay out 10 of the flour tortillas. You will need to make sure that they are overhanging all sides of the sheet tray by at least 2-3 inches. You will also want to make sure that there are no gaps or open spaces between the flour tortillas. It should look like a solid layer of flour tortillas with all the sides overhanging. The part of the flour tortillas that are overhanging will be used to fold over and seal the sheet pan tacos once assembled.

Step 6

Using a large slotted spoon, spoon the ground beef mixture evenly over the flour tortillas. Make sure to allow as much of the fat from the ground beef mixture to drip off through the slotted spoon before placing the meat onto the tortillas. This ensures that you don’t have soggy tortillas when baked.

Step 7

Sprinkle the shredded Colby jack cheese evenly over the top of the ground beef layer.

Step 8

Finally, using a slotted spoon, spoon 1½ cups of the pico de gallo over the top of the cheese. You will want to make sure that you allow as much of the juices from the pico de gallo to drain out before layering it onto your cheese.

Step 9

Place your final 6 flour tortillas, overlapping each other in the center of your sheet tray, onto the top of the meat and cheese. Fold the overhanging flour tortillas over the top six tortillas so that you are enclosing all the meat and cheese.

Step 10

Brush the remaining 2 tablespoons of canola oil evenly over the tops of all the flour tortillas. You can use the oil to help the top overhanging pieces stick to each other.

Step 11

Place the second 13x18-inch rimmed sheet baking tray onto the top of the sheet pan taco making sure that all the folded-over tortillas stay in place. Place 1 or 2 oven-safe heavy skillets, like cast iron, onto the sheet tray to weigh it down. This will create a nice sealed sheet pan taco. It also helps to ensure that the flour tortillas become crisp and golden brown. Bake for 30 minutes. Carefully remove the heavy skillet(s) and the top sheet tray. Continue to bake the sheet pan taco for an additional 30 minutes or until the top is golden and crisp. You may want to tent your 4 sides with long strips of aluminum foil (like you would a pie crust when baking) to ensure that the edges do not get too dark before the center of your sheet pan tacos get nice and golden.

Step 12

Allow the sheet pan taco to rest for 5-10 minutes before slicing and serving.

Step 13

You can garnish your individual servings of this sheet pan taco with a dollop of sour cream and a spoonful of the remaining pico de gallo. You can keep your sheet pan taco warm by covering it with a piece of aluminum foil and keeping it in a 200°F oven for up to 30 minutes.

Step 14

In a large bowl, add the diced tomatoes, chopped white onion, fresh lime juice, finely diced jalapeño, and chopped cilantro. Stir to combine the pico de gallo. Cover with plastic wrap and refrigerate. This allows all the flavors of the pico de gallo to combine while you are preparing the rest of the sheet pan tacos.