1. Peel the sweet potatoes and cut into large chunks.  Add to a pot of boiling water and boil for 20 minutes or until fork tender. Drain and mash with a potato masher.
2. For the sweet potato filling
3. Preheat your  oven to 375 and spray a 9x13 with cooking spray.
4. To the hot, mashed sweet potatoes add the milk and 1/2 cup butter. If using unsalted butter then add a pinch of salt and this point. Add the sugar and vanilla and stir until combined.  If the mixture is still too hot then set aside and let cool for a bit before adding your two eggs (you don't want to accidentally scramble your eggs if your mixture is too hot!). When slightly cool add your two eggs. Evenly spread into your sprayed 9x13 and set aside while you make the topping.

Streusel topping:

1. In a separate bowl mix together the flour and brown sugar.  Cut in your cold butter until coarse crumbs.  Mix in those pecans and evening sprinkle on top of your sweet potato mixture in the 9x13.
2. Bake uncovered at 375 for 25 minutes until the top is all golden and crispy. If it isn't browning well you can broil at the end for 2-3 minutes, watching very closely! Reheats perfectly for Thanksgiving leftovers!