In a large bowl, add the warm water, yeast, and 1 tablespoon of sugar. Whisk to blend and let sit for 7-10 minutes until a 'raft' forms on the top of foamy-looking yeast.

Add the remaining sugar, melted butter, egg, egg yolk, and buttermilk to the yeast mixture and whisk to combine.

Add the flour and salt, and using a hand mixer or stand mixer with a hook attachment, blend until the flour is combined with the liquid and the dough becomes smooth.

If using a hand mixer, remove the dough from the bowl once blended and knead by hand for about 5 minutes until smooth and less sticky.

Spray the bowl with cooking spray and let the dough rise covered in plastic wrap or a clean towel for about 90 minutes until doubled in size.

Lightly flour a flat surface and roll the dough out to a rectangle that is 1/2 inch thick.

Cut the dough into 2 inch by 3 inch rectangles and place them on a platter to separate for frying.

Fill a large deep pan with grapeseed oil, about 2-3 inches deep. Bring the oil to 350F.

Gently add 5-6 pieces of beignet dough to the oil and cook for about 2 minutes on each side until puffed and golden brown.

Remove with tongs and set on paper towels to catch excess oil. Continue until all beignets are cooked.

Add the powdered sugar to a resealable bag, add 2-3 cooked beignets, seal, and shake gently to coat. Remove and serve immediately.