In a food processor, pulse pecans and vanilla wafer cookies until fine crumbs. Pour into a large bowl. Add brown sugar, corn syrup, and vanilla extract. Mix with a spoon until fully combined.

Using a one tablespoon scoop, drop scoops onto a parchment paper lined baking sheet (that is freezer safe). Once all scoops have been formed, roll each scoop into a nice smooth ball with your hands. Transfer baking sheet to freezer for about 30 minutes.

When ready, melt white chocolate and dark chocolate wafers in separate bowls according to package directions.

Using a toothpick, dip a cold truffle into either white or dark chocolate. Tap on the side of the bowl to remove excess. Place back on parchment paper, remove toothpick, and top with a pecan half (to cover the toothpick hole). Repeat until all truffles are dipped.

I like to work in two stages. It's easier if the truffles remain very cold. So I do half of them while the other half is still in the freezer. Then I work on the second half.