Beat the eggs until fluffy. In a seperate bowl, combine the pecans, brown sugar, & flour. Whisk the melted butter into the pecan mixture followed by the beaten eggs. Stir in the vanilla extract.
Spray the inside of your crockpot with nonstick cooking spray. Pour the batter into your crockpot. Cook on high for 2 hours. It should be very moist when done! Best served warm with vanilla ice cream! ;)