Whisk the ricotta, heavy cream, and zest if using in a mixing bowl until combined. Add in the ¼ teaspoon of salt and a few cranks of black pepper. Taste the ricotta and adjust the seasoning as necessary.
Preheat the oven to 425°F. Lay the baguette slices out on a sheet pan and drizzle each with a little olive oil. Toast until they are golden brown, about 6 minutes.
Slice the figs into rounds discarding any hard tips. Spread the ricotta mixture over the toasted baguette slices and layer 1 piece of prosciutto and 1-2 fig rounds per crostini. Drizzle each crostini with honey and season with thyme leaves, freshly cracked black pepper, and flaky sea salt.