If you don't mention it, no one will ever suspect that this incredible chocolate dessert, with its smooth texture and rich flavor, is made with beets.
Preheat oven to 350°.
Weigh or lightly spoon almond meal flour into a dry measuring cup; level with a knife. Place almond meal flour in a food processor; pulse 10 times or until very finely ground. Combine almond meal flour, 1/2 cup sugar, and next 4 ingredients (through salt) in a medium bowl; stir with a whisk.
Combine chocolate and butter in a small microwave-safe bowl; microwave at HIGH 1 minute or until melted, stirring after 30 seconds. Stir until smooth.
Place chocolate mixture, beets, canola oil, 1 teaspoon vanilla, and eggs in a food processor; process until smooth. Add flour mixture; process 30 seconds or until smooth.
Pour batter into an 8-inch springform pan coated with cooking spray, spreading evenly. Bake at 350° for 50 minutes or until a wooden pick inserted in center comes out clean. Cool 5 minutes in pan on a wire rack; remove sides of pan. Cool completely on wire rack.
To prepare topping, combine sour cream, 2 teaspoons sugar, and 1/4 teaspoon vanilla in a small bowl; stir with a whisk until smooth. Serve blueberries and topping with cake.