Grilling the fish makes it moist and tender.
6 tablespoons mayonnaise
5 tablespoons minced fresh basil
1 teaspoon grated lemon peel
3 tablespoons olive oil
1 tablespoon fresh lemon juice
4 5- to 6-ounce skinless salmon fillets (each about 3/4 inch thick)
8 bacon slices
1 small red onion, sliced
8 1/2-inch-thick sourdough or country-style white bread slices (each about 5x3 inches)
8 tomato slices
8 lettuce leaves
Mix mayonnaise, 2 tablespoons basil and lemon peel in small bowl to blend.
(Can be made 1 day ahead. Cover and chill.)
Mix remaining 3 tablespoons basil, olive oil and lemon juice in large glass baking dish.
Add salmon to oil mixture; turn to coat.
Cover; chill 1 to 4 hours.
Cook bacon in heavy large skillet over medium-high heat until crisp.
Using tongs, transfer bacon to paper towels to drain.
Add onion to drippings in skillet.
Saut� until onion is tender and beginning to brown, about 5 minutes.
Prepare barbecue (medium-high heat).
Grill fish until just opaque in center, about 3 minutes per side.
Grill bread just until golden, about 2 minutes per side.
Spread mayonnaise mixture over 1 side of bread slices.
Top each of 4 bread slices with 2 bacon slices,
2 tomato slices, 1/4 of onion, 1 salmon fillet and 2 lettuce leaves.
Cover with remaining bread slices.
Makes 4 servings.