Preheat the oven to 375°F (190°C). Cook the jumbo pasta shells in a large pot of salted boiling water according to package instructions until al dente; drain and set aside to cool slightly.
In a large skillet over medium heat, cook the ground beef with the taco seasoning until browned and cooked through, about 6–8 minutes; drain excess fat and let the beef cool completely.
In a large bowl, combine ricotta, 2 cups of the Mexican cheese, chopped black olives, diced green chilies, garlic powder, onion powder, kosher salt, ground pepper, and cumin. Stir to combine.
Add the cooled ground beef to the ricotta mixture and mix until evenly distributed.
Create a well in the center of the mixture and add the eggs. Lightly beat the eggs, then mix them into the filling until smooth and uniform.
Spoon the filling into a piping bag or a resealable plastic bag with a corner snipped off and pipe the filling into each cooked shell, or fill with a spoon.
In another bowl, whisk together the enchilada sauce and heavy cream until smooth.
Spread half of the sauce mixture in the bottom of a 9x13-inch baking dish. Arrange the filled shells side by side in the dish. Pour the remaining sauce evenly over the shells, then sprinkle the remaining 2 cups of Mexican cheese over the top.
Bake in the preheated oven until the cheese is bubbly and the casserole is heated through, about 25 minutes. Remove from the oven and let cool slightly before serving.