Pre heat the oven to 350 degrees.
Grease two 12 count mini muffin pans.
Add hazelnuts to a baking sheet. Toast in the oven for 8 - 10 minutes or until golden brown.
Rub skins off and let cool.
Add the hazelnuts to a food processor.
Add the flour and salt and pulse until the mixture is finely ground.
Add the butter to a small saucepan and cook until the butter foams and then browns, about 6 - 8 minutes.
When cool, stir in the vanilla.
Increase oven temperature to 400 degrees.
Combine the honey, orange juice and zest in a small saucepan and gently heat. Stir to combine.
Remove from heat and set aside.
In a large bowl, whisk the egg whites.
Add the brown sugar and whisk until smooth.
Fold in the flour/hazelnut mixture in two additions, making sure all the flour has been incorporated before adding more.
Fold in the butter.
Evenly divide the batter between the muffin tine and bake for 10 - 15 minutes or until a tester comes out clean.
After removing from the oven let cool for 5 minutes and then remove the cakes to a cooling rack.
Using a pastry brush, glaze the mini cakes with the orange and honey mixture.