Preheat the oven to 350 degrees.
Blind bake your crust filled with pie weights or dry beans for 15 minutes.
Remove the crust and gently prick holes it in with a fork, then brush it with an egg wash (one egg beaten with 1 tbsp of water or milk)
Bake the crust for another 10-15 minutes until golden brown. Remove crust from the oven and allow it to cool while making the filling
Place the sweet potato banana purée in the bowl of a stand mixer fitted with the paddle attachment and beat it on high for 1-2 minutes.
Add the sugar and beat for 2 more minutes to combine, scraping down the bowl as needed.
With the mixer on low, add the eggs one at a time and mix until incorporated.
Add the evaporated milk and mix on medium for 1-2 minutes until well combined.
Add the cinnamon, nutmeg, salt, and vanilla and mix on medium for another minute; reduce the speed to low and slowly add the melted butter.
Once all the butter is added, put the mixer on high and beat for an additional minute.
Scrape down the bowl one last time and make sure everything is well combined.
Cover the outer crust of the pie with a strip of folded aluminum foil, so it does not burn.
Pour the filling into your pie shell and bake at 350 for 35-45 minutes or until a tester inserted in the center comes out clean.