Cook the Mexican rice according to the package directions. While the rice is cooking, you will prepare the ground beef and the other filling ingredients.

In a large skillet, on medium-high heat, add the unsalted butter and chopped onions. Cook the onion for 1-2 minutes or until the onions are soft.

Add the lean ground beef to the skillet and cook the beef for 7-8 minutes or until browned and cooked through. Drain any excess fat from the skillet.

Turn the heat down to medium-low and add the water, the packet of taco seasoning, salt, and black pepper to the ground beef. Stir to coat all the ground beef with the seasonings. Cook for another 4-5 minutes or until the liquids have reduced and the ground beef is completely coated in taco seasoning sauce. Remove from the heat.

To assemble each burrito, you will lay one large flour tortilla onto a plate. In the bottom third of the tortilla, add ½ cup of prepared Mexican rice. You will want to spread it into an even layer but avoid going all the way to the edge. You will use the edges to fold up your burrito.

Top the rice layer with ½ cup of the seasoned ground beef, followed by 1½-2 tablespoons of the warmed nacho cheese sauce, then a handful (about ¼ cup) of Fritos corn chips. You will want to make sure that you are not overfilling your flour tortilla, or it will be very difficult to fold up.

Once you have added all your filling ingredients (including any of the optional ones suggested in the tips), you will fold the bottom portion of the tortilla up and over the filling ingredients.

Next, you will fold both sides of the flour tortilla up to meet the filling ingredients.

While holding the folded-up sides of your tortilla, you will very gently roll the tortilla up, starting from the bottom and rolling towards the top until your filling is all enclosed into the large flour tortilla.