Combine all the ingredients for the sauce in a medium saucepan and bring to the boil over medium-high heat. Reduce to a slow simmer, cover loosely and cook for about 30 minutes, stirring from time to time. Meanwhile, prep the rest of the ingredients and preheat your oven to 375°F.
Pour about 1/3 of the sauce at the bottom of a 9" x 13" lasagna baking dish and spread to cover the bottom of the dish. Top with 1/2 the chicken, 1/2 the corn, 1/2 the black beans, 1/2 the tortillas and 1/4 of the grated cheese.
Repeat with a second layer but this time, do 1/3 the sauce, the rest of the chicken, the rest of the corn, the rest of the black beans, 1/4 of the cheese and 1/2 the jalapeno peppers.
Finish with the rest of the tortillas, the rest of the sauce, the rest of the cheese and the rest of the jalapeno peppers.
Bake uncovered in the preheated oven for 30 minutes. Remove and garnish with a handful of chopped cilantro, diced avocado, diced tomato and sliced green onions.