Line a 9 x 13 inch baking pan with a silicone mat or tin foil sprayed with non-stick spray.
Preheat your oven to 350 degrees Fahrenheit.
Arrange the Ritz crackers in rows on the prepared baking sheet.
In a saucepan, combine the butter, brown sugar, and vanilla. Heat over medium-high heat until simmering, then let it simmer for 5 minutes.
Pour the toffee mixture evenly over the crackers and spread it out with an offset spatula.
Bake the toffee-covered crackers for 5 minutes in the oven.
Remove from the oven and sprinkle the chopped dark chocolate over the crackers.
Return to the oven and bake for 3-5 minutes, or until the chocolate is melted.
Spread the melted chocolate evenly across the crackers with an offset spatula.
Chill the baking sheet in the fridge for 30 minutes, or until the chocolate and toffee are hardened.
In a microwave-safe bowl, melt the white chocolate in 30-second intervals, stirring after each, until completely melted.
Stir in the peppermint extract into the melted white chocolate until combined.
Pour the melted white chocolate over the hardened dark chocolate layer and spread it out evenly.
Sprinkle the crushed candy canes over the white chocolate while it's still melted.
Return the baking sheet to the fridge and chill for another 30 minutes, or until the white chocolate is hardened.
Once everything is set, break the peppermint bark apart and indulge!
Store any leftovers in a bag or airtight container in the fridge for up to 1 week or in the freezer for 2 weeks.