Chocolate Walnut Mug Cake

Ingredients (10)

• 1.5 tsp stevia powder
• 0.25 tsp baking powder
• 2 tbsp white whole-wheat flour
• 2 tbsp unsweetened cocoa powder
• 0.25 tsp vanilla extract
• 1 Nonstick cooking spray
• 0.75 tbsp walnuts chopped
• 1 pinch pinch salt
• 1.5 tsp canola oil
• 2 tbsp skim milk