Sprinkle with toasted almonds for added crunch and colour
Remove pan from the heat and gently whisk in butter and vanilla. Return pan to the heat and cook until custard is thick and almost pudding-like. Remove from the heat and allow the custard to cool in the pan to room temp. Transfer custard to a bowl and gently press plastic wrap onto the surface of the custard. Refrigerate for 1 hour to overnight, preferably.
In a medium saucepan, combine cardamom, cinnamon stick (if adding), wine, sugar, lemon juice and salt. Cook over medium heat, stirring until the sugar dissolves.
Add the pears into the poaching syrup and add enough water to completely submerge the pears. Bring mixture to a simmer, turning occasionally, until pears are tender but not mushy, about 25-30 minutes. Using a slotted spoon, transfer the pears to a plate to cool. Wait until pears have cooled to room temperature before placing on the tart.
Spoon roughly ¾ of the custard mixture into the cooled tart shell. The other ¼ you transfer to a small dish and save for later (tip: this custard is delicious topped with granola and blueberries for a morning on the go!). Top the custard with the cooled poached pears. Sprinkle toasted slivers of almonds and dust with confectioners’ sugar and serve.