Prepare the Mushrooms: Preheat your grill (or oven to 375°F/190°C if baking). Clean the portobello mushrooms by gently wiping them with a damp paper towel. Remove the stems and gills to create space for the filling.

Season and Grill the Mushrooms: Brush both sides of the mushrooms with olive oil and sprinkle with a pinch of salt. Place the mushrooms gill-side up on the grill (or baking sheet if using the oven) and cook for 5-7 minutes until they start to soften.

Prepare the Filling: In a medium bowl, mix the corn, black beans, enchilada sauce, salt, and flour. Stir until well combined. The flour will help thicken the filling slightly.

Stuff the Mushrooms: Evenly distribute the enchilada filling between the four portobello mushrooms, spooning it into the mushroom caps. Top each mushroom with shredded mozzarella or Monterey Jack cheese.

Grill or Bake the Mushrooms: Return the stuffed mushrooms to the grill (or place them in the preheated oven) and cook for another 8-10 minutes, or until the cheese is melted and bubbly and the mushrooms are tender.

Garnish and Serve: Remove the mushrooms from the heat and garnish with freshly chopped chives. Serve hot, and enjoy these flavorful enchilada-stuffed mushrooms as a main course or a hearty side!