Prepare Cilantro-Lime Mayonnaise. Cover and chill until ready to serve. Carefully clean lump crabmeat, removing any shell or cartilage pieces. Cut the cooked spaghetti into 1-inch pieces; set aside.
In a large bowl combine the eggs, green onions, bread crumbs, cilantro, serrano peppers, the 2 teaspoons oil, the salt, and black pepper. Add crabmeat and spaghetti pieces; mix well. Shape into 12 patties, about 1/2 inch thick.
In a large heavy skillet heat the 2 tablespoons oil over medium heat. Cook patties, a few at a time, in hot oil about 6 minutes or until golden brown, turning once. Drain on paper towels. Cover and keep warm in a 300 degree F oven while cooking the remaining patties.
Serve the crab cakes with the cilantro mayonnaise and, if desired, lime and/or lemon wedges. Makes 6 servings (12 crab cakes).
In a small bowl combine light mayonnaise dressing or salad dressing, fresh cilantro, lime peel, and lime juice. Makes 1/2 cup.