This piquant, ham-and-shrimp-studded filling will work with large zucchini as well. For zucchini, simply skip the boiling step and bake as described. If desired, substitute 3 ounces cooked crabmeat or crawfish tails for the shrimp.
Boil in salted water to cover until tender but firm, 6 to 10 minutes:
Drain and set upside down on a rack to cool. Scoop out the insides, leaving roughly ⅜-inch-thick shells. Pat the shells dry and place in a 13 × 9-inch baking dish. Chop the pulp.
Preheat the oven to 375°F.
Heat in a large nonstick skillet over medium-high heat:
Add and cook, turning once, until bright pink, about 2 minutes:
Remove the shrimp and let cool. Add the squash pulp to the skillet along with:
Cook, stirring, until the vegetables are softened, about 4 minutes. Meanwhile, finely chop the shrimp. Remove the filling from the heat and stir in the shrimp. Divide among the squash shells and sprinkle with:
Bake until heated through and browned on top, about 35 minutes.