Preheat oven to 325°F (160°C) and spray an 8" square pan with nonstick spray.
Mix flour, cinnamon, baking soda, and salt. In a separate bowl, whisk melted butter, milk, egg white, and vanilla. Stir in honey and stevia. Combine with dry ingredients.
Press dough into pan and bake for 10-12 minutes. Cool completely.
Prepare frosting by beating yogurt, cream cheese, pudding mix, cinnamon, and stevia for 2 minutes. Chill for 2 hours.
Spread frosting over cooled bars and slice into 16 squares.
Notes
Chill the frosting for best consistency and flavor.