Preheat the oven to 220˚C (425˚F)
In bowl, gently toss the strawberries, sugar, vinegar and pepper; set aside.
Place baguette slices on baking sheet. Brush tops with oil. Bake until golden and crisp, about 4 min., check frequently to avoid scorching. Remove from oven; cool slightly.
Spread bread with mascarpone. Top with strawberry mixture. Drizzle with a little leftover syrup from the bowl and honey. Sprinkle with hazelnuts. Serve immediately.