Preheat the oven to 350°F. Butter and flour a 9-inch springform pan or spray liberally with baking spray. Set aside.
Using an electric mixer cream together the butter, both sugars and vanilla extract. Beat for 2 minutes on medium-high speed stopping to scrape the sides of the bowl periodically until fluffy and light beige in color.
Add the pumpkin beating until incorporated..
Add the eggs one at a time beating well after each addition.
In a separate bowl, sift together the flour, pumpkin pie spice, baking powder and salt.
Lower the speed of the mixer and add the sifted dry ingredients alternately with the sweetened condensed milk beginning and ending with flour.
After all has been added beat for about 30-45 seconds.Scrape the sides and bottom of the bowl.
Pour the batter evenly into the prepared pan. Bounce gently to release trapped air.
Place into the oven and bake for 60-70 minutes (1 hour to 1 hour 10 minutes) or until a toothpick inserted into the center shows moist crumbs. Do not over bake. Check at 45 minutes and lay a piece of aluminum foil on top to prevent over browning, if needed.
Cool in the pan for 10 minutes then remove the outer ring. Cool to room temperature on a cooling rack.
Serve drizzled with Bourbon Pecan Praline Sauce and whipped cream, if desired.