Begin by heating a large skillet over medium heat and adding a drizzle of cooking oil.

Toss in the diced onion and sauté until it's translucent, about 3-4 minutes.

Stir in the minced garlic and let it cook for another minute until fragrant.

Increase the heat to medium-high and add the ground beef. Cook, breaking it apart, until it turns rich brown, about 5-7 minutes.

Add salt and pepper to taste, ensuring those flavors meld beautifully.

Carefully drain any excess fat from the skillet.

Sprinkle the taco seasoning over the beef, followed by 1 cup of water. Stir to combine and let simmer for about 5 minutes.

In a large bowl, combine the cooked rice, diced tomatoes, and half of both the cheddar and Monterey Jack cheese.

Fold the meat mixture into the bowl and mix until everything is evenly incorporated.

Lay a flour tortilla flat and spoon about ⅓ cup of the beefy filling into the center.

Top with a dollop of sour cream and a sprinkle of cilantro if using. Fold the sides inward and roll tightly.

Preheat a skillet over medium heat and place each burrito seam-side down.

Cook for about 2-3 minutes on each side until golden brown and slightly crispy.

Remove each burrito, sprinkle with remaining cheese, and cover with a lid for about a minute to melt.

Serve warm with extra sour cream, salsa, or guacamole.