Melt white chocolate chips by microwaving in a glass container for 30 seconds at a time, stirring and microwaving again until melted.
Stir in broken pretzels. Add additional pretzels if you'd like a crunchier candy.
Pour onto parchment paper or aluminum foil and spread out to the thinness you desire your candies to be.
Sprinkle holiday M&M's over the white chocolate immediately before the chocolate starts to harden. Press M&M's down lightly to make sure they connect with the chocolate, otherwise some of them will not attach to the chocolate and will come loose when you break the candy into pieces.
Let harden on the counter, or place in refrigerator for about an hour. Once hardened, either cut or break into pieces.