Preheat the oven to 400 degrees F.
On a slight bias, slice the baguette into 1/4-inch slices. Brush the slices with the 1/4 cup olive oil, then place on a baking sheet and sprinkle with the 1/2 teaspoon salt. Bake until golden brown and crunchy, 10 to 12 minutes. Set aside to cool.
In a small bowl, whisk together the ricotta, lemon zest, 3 tablespoons olive oil, and 1/8 teaspoon salt.
Once the crostini are cool, top each with 1 heaping tablespoon of ricotta mixture, a pinch of coarse salt and a sprinkling of crushed pink peppercorns. Serve at room temperature.