Add the milk, yeast, and sugar to the bowl of a stand mixer. Stir and then let it bloom for a few minutes.

Whisk in the eggs, vanilla, and salt. Attach the dough hook to the mixer. Mix on low speed while gradually adding in the flour.

Continue to mix on low for 3-4 minutes until the dough becomes smooth and elastic and pulls away from the sides of the bowl.

Remove the dough from the mixer and place on the counter to knead a few times and shape into a ball.

Wrap in plastic wrap and chill in the refrigerator for 30 minutes.

On a floured surface, roll out the dough to a 12×18-inch rectangle. Visually divide the dough into thirds.

Spread 7 tablespoons of butter onto the middle portion of the dough.

Fold one side on top of the buttered middle third. Spread the rest of the butter on top of the folded side.

Fold the remaining side inward on top of the 2nd buttered portion.

Place the dough on a baking sheet, cover with plastic wrap, and refrigerate for another 30 minutes.

Roll out the dough into a rectangle about the same dimensions as before. Fold the dough using the same pattern as before, turning each third inward over the middle third.

Place on the sheet pan, cover and refrigerate for 30 minutes.

Repeat the process of rolling to a rectangle and folding inward 2 more times.

Place the dough back on the sheet pan, cover, and refrigerate for at least 1 hour.

Roll out the dough to a little under ½-inch thick.

Use a donut cutter, round cookie cutter, or jar to cut out 8-10 circles. Use a smaller round cookie cutter to cut out the holes in the circles.

Place the donuts and donut holes on a lined baking sheet.

Add 2-3 inches of oil to a Dutch oven and heat to 350°F.

Working in batches (2-3 at a time), drop the donuts into the oil and fry for a couple minutes on each side until golden brown. Transfer to a baking rack or baking sheet lined with paper towel.

Whisk together the glaze ingredients.

Dip the top of each cronut in the glaze. Return to the rack to allow the glaze to set.