Set oven to 350°F (175°C). Grease or line an 8×8-inch pan with parchment paper.
In a bowl, whisk melted butter and brown sugar until smooth. Add egg, honey, and vanilla extract; whisk again.
Gently stir in flour, salt, and ½ teaspoon cinnamon until just combined. Do not overmix.
In a small bowl, combine granulated sugar and remaining ½ teaspoon cinnamon.
Pour batter into prepared pan and sprinkle evenly with cinnamon-sugar mixture. Bake for 22–25 minutes until golden brown and a toothpick comes out clean.
Let blondies cool fully before cutting into squares for neat slices.