Preheat oven to 375°F. Arrange baguette slices on a baking sheet and brush lightly with olive oil. Toast for 8–10 minutes, until golden and crisp.
In a food processor, place the ricotta, olive oil, lemon juice, and process until light and smooth, 1 to 2 minutes.
Spread each crostini with a generous layer of ricotta.
Top with pear slices and small ribbons of prosciutto.
Drizzle with honey or balsamic glaze and garnish with thyme or rosemary.
Serve immediately — best enjoyed warm or at room temperature.