Hands on: 20 minutes Total time: 1 hour, 20 minutes
No need for expensive white chocolate, white chocolate chips will work fine. Store the truffles in the refrigerator before your party and serve at room temperature.
1 cup (about 6 ounces) white chocolate chips
2 tablespoons unsalted butter
1 tablespoon heavy cream
Pinch of salt
1 tablespoon liqueur, optional
2 tablespoons powdered sugar
Red food coloring
12 whole walnuts
In a medium saucepan over low heat, warm chocolate, butter, cream and salt until chocolate is just melted. Remove from heat and be sure everything is well mixed. If you're using liqueur, stir it in now. Set aside 1/2 cup.
Transfer remaining chocolate mixture to a small bowl, cover and refrigerate until firm enough to scoop, about 1 hour.
While chocolate is firming, stir food coloring into reserved chocolate mixture until you have the desired color. Arrange walnuts on a wire rack over a piece of parchment paper. Spoon colored chocolate over walnuts to cover. Allow chocolate to set. Put walnuts aside until ready to make truffles.
Use a teaspoon or small cookie scoop to make 1-inch truffles. Roll each truffle in powdered sugar, then top each with a walnut brain. Store truffles in refrigerator for up to 1 week.