In a heavy-bottomed pot over medium heat, combine the granulated sugar, brown sugar, evaporated milk, and butter.
Bring the mixture to a boil and let it boil until it reaches 240°F on a candy thermometer, which is the soft ball stage.
Remove the pot from heat and let it cool for 5 minutes.
Stir in the vanilla extract and pecans.
Using a wooden spoon, beat the mixture until it loses its shine and begins to thicken.
Drop spoonfuls of the mixture onto a parchment-lined tray.
Allow the pralines to cool completely and set.
In a microwave-safe bowl, melt the red candy melts in 30-second intervals until smooth.
Repeat this process with the green candy melts.
Transfer the melted red chocolate to a piping bag or a zip-top bag with a corner snipped off.
Do the same with the green candy melts.
Drizzle the red and green melted chocolate over the pralines.
Let the chocolate set.
Serve!