How to Make It
In a skillet, toast the pine nuts over moderate heat, shaking the pan, until golden brown, 3 minutes; let cool. In a food processor, process the flour, sugar, vanilla seeds and pine nuts until the pine nuts are coarsely ground. Add the butter and process until pea-size clumps appear. Add the egg yolks and whole egg and process just until blended. Scrape the dough out onto a lightly floured work surface and knead just until it comes together. Pat into a disk, wrap in plastic and refrigerate until firm, about 1 hour.
Preheat the oven to 375°. On a floured work surface, roll out the dough to a 9-inch round. Transfer to an 11-inch tart pan with a removable bottom. Press the dough into the pan and up the sides. Trim the overhang. Refrigerate the tart shell until firm, about 30 minutes.
Line the tart shell with foil and fill with pie weights. Bake for 25 minutes, or until dry and lightly browned around the edge. Remove the foil and weights and bake for 20 minutes longer, until crisp and golden. Transfer to a rack to cool.
In a bowl, using an electric mixer, beat the ricotta, cream cheese, vanilla seeds, mascarpone and crème fraîche at moderate speed until smooth. Beat in the sugar and honey. Add the eggs, 1 at a time; beat well after each addition. Beat in the thyme, lemon zest and a pinch of salt. Pour the filling into the tart shell and bake for 30 minutes, or until just set and a little wobbly. Transfer to a rack to cool completely.
In a saucepan, bring the honey to a boil over moderately high heat. Remove from the heat and let cool to warm, 10 minutes. Stir in the thyme and lemon zest, then pour the glaze over the tart. Serve at room temperature or chilled. Alternatively, slice the tart and drizzle with the honey.