Combine cream cheese and sour cream in a small bowl. Set aside.
Heat oil in large skillet over medium heat. Add zucchini, mushrooms, garlic powder, basil, Beau Monde seasoning and pepper; stir-fry until tender, about 4 to 5 minutes. Add shrimp and crab; heat through.
Spread 5 tortillas with an equal amount of the cream cheese mixture (about 1-1/2 tablespoons per tortilla). Top each with 1/2 cup stir-fry, then sprinkle with 2 tablespoons Gouda. Lightly press a tortilla on top.
Place skillet over high heat. Transfer 1 quesadilla to the skillet, and cook for 1 to 2 minutes on each side. Repeat with the remaining quesadillas. Serve hot.