1 teaspoon salt
1 teaspoon dried thyme leaves
1 teaspoon dried oregano leaves
1/2 teaspoon black pepper
1/4 teaspoon cayenne pepper
1/4 teaspoon white pepper
4 medium to large mirlitons
4 tablespoons butter, divided
2 tablespoons olive oil
1 medium onion, chopped
1 medium green bell pepper, chopped
1 stalk celery, chopped
2 garlic cloves, minced
1 pound small (41 or higher count) to medium (26-40 count) shrimp, peeled, deveined and chopped
1 1/2 cups Italian bread crumbs, divided
FOR SEASONING MIX: In a small bowl, thoroughly combine seasoning mix. Set aside.
FOR MIRLITONS: Place whole mirlitons in a large pot of cold, salted water. Bring water to a boil; cook mirlitons in boiling water until just fork-tender, about 20 minutes. Drain and cool. Once mirlitons are cool enough to handle, slice each one in half; remove and discard seeds. Gently scoop out pulp, leaving skins intact with enough meat to hold its form. Drain mirliton shells upside down on paper towels. Chop pulp into bite-size pieces; place in a colander to drain. Set aside shells and pulp.
FOR STUFFING: In a large saucepan over medium heat, melt 2 tablespoons butter with the olive oil. Add onions, bell pepper, celery and garlic; sauté until tender, 5-7 minutes. Stir in shrimp; cook until shrimp turn pink, about 5 minutes. Reduce heat to low. Add seasoning mix and reserved mirliton pulp. Cook an additional 5 minutes. Remove shrimp mixture from heat. Stir in 1 cup bread crumbs to absorb the liquid (mixture should be moist but not runny; may need to add more bread crumbs). Adjust seasoning if necessary.
CONSTRUCT: Spoon shrimp & militon mixture evenly into mirliton shells. Place stuffed mirlitons in a large, lightly greased baking dish. Sprinkle tops with reserved breadcrumbs and butter. At this point, the stuffed mirlitons can be wrapped individually in plastic wrap, placed in freezer bags and frozen for later use. Simply thaw them at room temperature before baking.
BAKE: Preheat oven to 350 degrees. Dot each mirliton with a small pat of butter. Bake, uncovered, until bubbly and tops are golden brown, about 20 minutes.