In a large bowl, whisk together the flour, sugar, baking powder, cinnamon, and salt.
In another smaller bowl, whisk together the milk, butter, eggs, and vanilla extract. Pour the wet ingredients into the bowl with the dry ingredients and whisk until smooth. Let sit for 5 minutes while preheating the waffle iron.
Heat the waffle iron as directed by manufacturer instructions. Once heated, scoop ½ cup of the batter into the waffle iron and cook according to manufacturer instructions. Repeat with the remaining batter.
In a small bowl, mix together the ½ cup sugar and 1 tbsp ground cinnamon for the topping.
Brush each waffle with the melted butter and immediately sprinkle with the cinnamon sugar mixture. Repeat on the other side of the waffles for extra cinnamon sugar flavor, if desired.
Serve warm with whipped cream and sliced strawberries!