Bloom your yeast by whisking in active dry yeast into water warmed to around 100 degrees Fahrenheit. Let sit for 10 minutes or until it starts to get foamy on the top.
In a medium sized mixing bowl, add bread flour, granulated sugar and fine sea salt. Whisk until incorporated. Add in your bloomed yeast mixture, 1 egg yolk and unsalted melted butter. Mix with a spatula until it begins to form a dough, then knead lightly.
Shape the dough into a ball and place back into the bowl. Cover with plastic wrap and let it rest in the fridge for 10 minutes.
Perform 'first turn' by stretching and folding the dough. Repeat for a total of two turns, resting in the fridge for 10 minutes between each.
Wrap the dough in plastic wrap and let it rest in the fridge for 25 minutes.
Roll the dough into a 7-inch by 7-inch square and place in the fridge overnight.
Prepare the Beurrage by pounding out the butter into a 4x4 inch square and chilling.
Flatten the dough, encase the butter, and roll into a long rectangle.
Perform folds and rest the dough in the fridge as needed.
Shape the croissants by cutting triangles and rolling them up.
Proof the croissants and bake at specified temperatures.
