Cover a large baking sheet with wax paper (I recommend wax paper, but parchment sprayed with nonstick spray will work in a pinch!)
Spread the broken cookies, pretzels, peppermint chips, and about ¾ of the M&M's onto the baking sheet.
7 Red Holiday Oreos, 7 Cool Mint Oreos, 1½ cups stick pretzels, ½ cup mint M&M's, ½ cup peanut M&M's, ½ cup peppermint baking chips
Place the white chocolate in a microwave-safe container and microwave for 1½ minutes on medium power. Stir and then microwave for another minute until melted and smooth. Watch it carefully to make sure it doesn't burn
1 pound white chocolate baking bars
Pour the melted chocolate over the cookie/candy mixture, spreading with a spatula if needed to coat completely.
Sprinkle the rest of the M&M's and red and green sprinkles over the still-wet chocolate. This wont work if it has hardened.
2 tablespoons red and green sprinkles
Chill the tray of bark until set and firm, about 1 hour. Remove and gently break bark into small pieces.