Begin by gathering all your ingredients, ensuring your veggies are fresh for the Easy Mexican Omelette. Chop the onions, red and green bell peppers, and ripe tomatoes into small pieces for even cooking. Rinse and drain the canned black beans, and if using sausage, prepare it now. This prep will set you up for a smooth cooking process.

In a skillet over medium heat, add a splash of cooking oil and sauté the chopped onions for about 2 minutes until they are translucent. Next, mix in the bell peppers and cook for an additional 2 minutes. Stir in the tomatoes, black beans, and cooked sausage if using, then sprinkle the ground cumin, smoked paprika, and optional chili powder. Cook everything together for 3-4 minutes, until heated through and fragrant.

In a mixing bowl, crack open your eggs and whisk them until fluffy, adding milk if desired for extra creaminess. Season with salt and black pepper, blending them into the egg mixture. This step ensures that your Easy Mexican Omelette will be light and flavorful, ready for cooking.

Heat a non-stick skillet over medium-low heat and add a small amount of butter or oil to prevent sticking. Pour in the egg mixture, tilting the pan to spread it evenly. Cook for 1-2 minutes, watching for the edges to set while gently lifting them with a spatula to allow uncooked egg to flow to the edges. You want a nice, fluffy base.

Once the edges of the omelette are set and the center is slightly runny, carefully spoon the filling you've prepared onto one half of the omelette. Sprinkle shredded cheese on top of the filling. Fold the other half of the omelette over the filling, then let it cook for an additional minute to melt the cheese inside.

Gently slide the Easy Mexican Omelette onto a plate, garnishing with fresh cilantro, avocado slices, and a side of salsa or pico de gallo for added zest. Serve with lime wedges for a bright flavor boost that complements your omelette beautifully.