In the bowl of an electric mixer, beat eggs until foamy. Beat in flour, sugar and brown sugar until well blended. Add in vanilla extract, pumpkin and pumpkin pie spice and mix until combined. Blend in melted butter with mixer on low speed, then gradually increase to high and beat until mixture is combined and you have a batter. Toss chocolate chips with a sprinkling of flour and fold into batter.
Pour into an unbaked 9-inch pie shell. Bake for 55 minutes, or until center is no longer jiggly.
Serve warm with ice cream of whipped cream.
Edited to add: I have tested this recipe four times and the measurements are correct. You MUST cool your butter completely. You also MUST use an electric mixer. And third, you MUST mix the butter in thoroughly with your electric mixer until a batter is formed like the first picture above. Feel free to add more pumpkin, but if you do that you will essentially have a pumpkin cake inside a pie crust. Other than that, the measurements are spot on. The key is you must, must, must let that butter cool.