Preheat the oven to 350°F. Line an 8x8-inch pan with parchment.
In a large bowl, whisk melted butter, coconut sugar, maple syrup, eggs, and vanilla extract until smooth.
Stir in flour, baking powder, cream of tartar, cinnamon, and salt until just combined.
Spread batter evenly into the pan. Mix the cinnamon topping and sprinkle it over the surface. You can play around with swirling lightly with a butter knife for a ribbon effect.
Bake 20 to 23 minutes, until edges are set and the center looks slightly soft.
Cool fully before slicing, and enjoy!
Notes
To keep their chewy texture, store the blondies in an airtight container at room temperature for three to five days.