Place colander in a 2-quart glass measure or medium bowl. Line colander with 4 layers of cheesecloth, allowing cheesecloth to extend over edge of colander. Spoon yogurt into colander. Cover loosely with plastic wrap; refrigerate 12 hours. Spoon yogurt cheese into a large bowl; discard liquid. Cover and chill.
Place parchment paper over a large baking sheet. Draw 3 (8-inch) circles on paper. Turn paper over, and secure with masking tape.
Preheat oven to 200°.
Beat egg whites and cream of tartar at high speed of a mixer until foamy; add black walnut extract. Gradually add 6 tablespoons granulated sugar, 2 tablespoons at a time, beating until stiff peaks form (do not underbeat).
Divide egg white mixture evenly among the 3 circles on the paper; using the back of a spoon, spread egg white mixture to fill the circles.
Bake at 200° for 2 1/2 hours or until dry. Turn oven off, and let meringues cool in closed oven at least 12 hours. Carefully remove meringues from paper; set aside.
Combine 8 whole strawberries and jelly in a small bowl; toss gently to coat. Drain strawberries, and discard remaining jelly. Place glazed strawberries on wax paper; set aside.
Add sour cream, 1/2 cup powdered sugar, and vanilla to yogurt cheese; stir well. Gently fold in quartered strawberries.
To serve, place 1 meringue circle on a serving platter, and gently spread with half of yogurt cheese-strawberry mixture. Top with another meringue circle; gently spread with remaining yogurt cheese-strawberry mixture. Top with remaining meringue circle; sift 2 teaspoons powdered sugar over top of torte, and garnish with glazed strawberries.