Line a 9" pie tin with a detachable base or a regular pie tin lined with foil. Grease the foil.
In a large bowl, mix the flours, sugar, baking powder, salt till combined. Add melted butter and gently bring together everything. Tip this onto the pie tin and smoothen with fingers to line enter base and the side of the tin, pressing down with a flat bottomed cup to even it out and chill in the fridge or freezer for 10-15 minutes.
Preheat oven at 170 C (325 F).
Place a rack in middle of oven and bake this crust for 20 minutes, until nearly golden.
Remove and brush with beaten egg all through and bake again for 5-7 minutes. This prevents the crust from becoming soggy.
While the crust is baking, prepare the filling.
In a large bowl, beat the eggs and sugar for 3-4 minutes till pale and thick. Lightly fold the yogurt and vanilla extract into this until mixed. Sieve the flour into this gently, folding it into the mix in batches. Once the crust is baked, pour the mix into it, it will reach almost to the top of the pan. Once you arrange the fruits in the center and nuts around the circumference, the tart is ready to go into the oven for 40 minutes at 170 C (325F), until lightly golden around the edges.
Unmould with the foil or from the detachable base and chill in the fridge for 2 hours or so. Peel off foil and place on a cake tray, slice into wedges. Once such tart will yield 16 slices.