1. Preheat the oven to 350 degrees F.

Crust:

1. Beat the butter and sugar until light and fluffy, approximately 3 minutes.
2. Add the eggs and the vanilla and mix well.
3. In a large bowl, sift together the flour, baking powder, and salt.
4. Mix the dry ingredients into the batter on low speed until just combined.
5. Press the dough evenly into an ungreased 9x13-inch baking pan, if the dough is too sticky, sprinkle lightly with flour. Bake for 15 minutes, until the crust is just set. Allow to cool, otherwise, when you add the filling it may let the crust.

Topping:

1. In a small bowl, add brown sugar, cornstarch and salt, whisk to combine.
2. Place a saucepan over low medium heat, add the sugar mixture to it.
3. Whisk in the egg yolks quickly, maple syrup and cream, until smooth. Stir continuously and bring to a simmer.
4. Reduce heat to low and cook until the mixture thickens like a pudding, 5-10 minutes. Stirring occasionally.
5. Remove from heat. Stir in the cold diced butter until fully melted.
6. Fold in roasted, chopped pecans and vanilla extract.
7. Pour over the crust, trying not to get the filling between the crust and the pan. Bake for 25 to 30 minutes, until the filling, is set.
8. Remove from the oven and allow to cool fully. Refrigerate until cold, for about 4-6 hours. Cut into bars and serve.