Preheat oven to 350ºF.

Combine almond flour, lupin flour, glucomann, monk fruit, and salt. Add in yolks, vanilla extract, and butter and mix until combined. Press into 9-inch tart pan (It will be just enough to provide a thin layer or a slightly thicker layer if you use an 8-inch tart pan). Prick all over with a fork. Line with well greased foil (buttered-side down). Fill with pie weights (rice works well) and bake at 350ºF for 15 minutes. Remove foil and bake another 8-10 minutes, until golden. Remove from oven and cool, leaving the oven on.

While the tart crust is cooking, prepare the filling. In a large bowl, cream the butter with monk fruit and glucomann powder. Stir in the syrup and eggs until smooth. Stir in the salt, vanilla, and pecan halves. Pour into the prepared pastry shell.

Bake for 30-40 minutes at 350ºF, or until the center has only a slight wobble when moved. Let cool completely before serving.