Score cut side of each eggplant half in a crisscross pattern; lightly coat cut sides of eggplant halves with cooking spray. Place eggplant halves, cut sides down, on a baking sheet. Bake at 425° for 10 minutes. Turn eggplant halves over; bake an additional 10 minutes or until tender. Remove from oven; cool 10 minutes. Remove pulp from eggplant, leaving a (1/4-inch-thick) shell. Place eggplant shells on baking sheet coated with cooking spray. Chop pulp; set aside.
Reduce oven temperature to 350°.
Heat olive oil in a large nonstick skillet over medium-high heat. Add ham, 1/2 cup onion, bell pepper, and garlic; sauté 5 minutes. Add reserved eggplant pulp and beer; cook 10 minutes or until most of liquid evaporates, stirring occasionally. Stir in shrimp; cook 1 minute. Remove from heat.
Place bread in a food processor; process until coarse crumbs form. Add breadcrumbs, 3 tablespoons cheese, green onions, basil, tarragon, rind, salt, and black pepper to eggplant mixture; stir gently to combine. Mound about 1/2 cup shrimp mixture into each eggplant shell. Sprinkle each with 1 1/2 teaspoons cheese. Bake at 350° for 15 minutes or until thoroughly heated and shrimp are done.