Heat oven to 400 degrees F. Grease and flour 9-inch round cake pan. Cut pear halves into thin slices.
In medium bowl, stir together Bisquick mix, sugar, milk and margarine. Pour into pan. Arrange pear slices in circular pattern on batter; sprinkle with cinnamon.
Bake about 40 minutes or until golden brown and toothpick inserted in center comes out clean. Top each serving with yogurt.