1 pound jumbo lump crabmeat, picked through for shells
Preheat oven to 375 degrees. Combine mayonnaise, half lemon zest, and lemon juice. Season with salt and pepper to taste. In another bowl, toss remainder of zest with crabmeat, being careful not to break up big lump pieces. Fold crab into mayonnaise mixture.
Slice baguette on an angle into sixteen pieces and arrange on a baking sheet. Brush with olive oil and season with salt and pepper. Bake until golden brown, about 10 minutes.
Spread crab salad on crostini and drizzle with additional olive oil before serving.