Follow the steps in order for the best result.
Begin by preheating your grill to a medium-high temperature.
In a small bowl, prepare the Cajun mayonnaise by combining the mayonnaise with 1 teaspoon of Cajun seasoning. Stir well and set aside for later.
In a large mixing bowl, thoroughly combine the ground sirloin, chopped jalapeno pepper, diced onion, minced garlic, 1 tablespoon of Cajun seasoning, and Worcestershire sauce. It's best to use your hands to ensure all ingredients are evenly distributed.
Divide the seasoned ground sirloin mixture into 4 equal portions. Shape each portion into a patty, flattening slightly.
Lightly oil the grill grates to prevent sticking. Place the patties on the preheated grill.
Cook the patties for approximately 5 minutes on each side, or until they are cooked through to your desired level of doneness. For food safety, ensure the internal temperature reaches 160°F.
In the last 2 minutes of grilling, place a slice of monterey jack pepper cheese on top of each patty, allowing it to melt slightly.
While the cheese is melting, spread the prepared Cajun mayonnaise on the inside of both halves of each hamburger bun.
Assemble the burgers by placing each cheesy patty on the bottom bun. Top with a lettuce leaf and a slice of tomato.
Cover with the top bun and serve immediately. Enjoy your homemade Tex-Mex burgers with a spicy kick!