Preheat oven to 425°F. Toss together grapes, thyme, fennel seeds, and 2 tablespoons oil on a small, rimmed baking sheet. Season with salt and pepper. Roast until slightly deflated and starting to brown, 20 to 25 minutes. Cool slightly.
Meanwhile, stir together ricotta, lemon zest, and remaining tablespoon oil in a bowl. Season with salt and pepper. Spread ricotta mixture on baguette, dividing evenly. Top with grapes, dividing evenly. Serve garnished with thyme leaves and drizzled with honey.
Keyword Roasted Grapes and Whipped Feta on Crostini