Preheat your oven to 350F.
In a large bowl, cream together the sugar and coconut oil using an electric mixer. Add the orange zest and orange juice and cream again. You'll need to cream at a high speed to get it fully mixed! Cream for about 2-3 minutes or until the mix is fluffy and lightly orange colored.
In a separate bowl, whisk together the flour, cornstarch, salt, and baking powder.
Gradually add the dry ingredients in with the wet, fold in to combine.
Line an 8x8' baking sheet with parchment paper, cut it to fit just the bottom. Grease the sides with any extra coconut oil or butter.
Place the orange slices on the bottom of the pan, thinly layering them so that they cover the entire bottom.
Add in the batter, it should be very thick, almost cookie-dough texture. Spread it out evenly with a spatula.
Bake at 350F for 25-30 minutes or until you can insert a toothpick and it comes out clean.
Let the blondies cool for 15 minutes, then flip the pan over to remove the blondies. Peel back the parchment paper to reveal the slightly caramelized (AKA "burnt") orange slices!
If you'd like, use a brush glaze the tops of the orange slices with simple syrup. This is totally optional but makes the blondies gorgeous!
Slice n' serve :)