Preheat oven to 350F. Arrange 18 slices of baguette on a baking sheet. Lightly brush or spray both sides of each slice with olive oil. Spread 1 cup walnut halves in 1 layer on another baking sheet. Place both sheets in oven and bake until nuts are toasted, about 6 min. Remove nuts to a rack to cool. Flip bread slices over and continue baking until lightly golden on both sides, about 4 more min. Cool completely. Just before serving, spread 150 g gorgonzola evenly over bread slices. Top each slice with walnuts and drizzle with honey.