Preheat oven to 350 F degrees
In a large bowl, cream together the butter and sugar then add the eggs one at a time.
Once all combined, add in the maple syrup, salt, and vanilla extract. This will expand and get a little foamy.
Prepare your pie crusts into greased muffin tins. Pour in batter 3/4 of the way and place in the oven.
After 10 minutes, take out of the oven and sprinkle a bit of the walnuts and pecans.
Place back in the oven for the remaining bake time.
Let the tarts cool then enjoy and serve!