Combine milk and water in a heatproof container and heat until 110-120F (43-49C). Pour into a large mixing bowl (or the bowl of a stand mixer), sprinkle yeast overtop and add a pinch (about 1 teaspoon) of your granulated sugar. Stir and allow to sit for 5-10 minutes, until the yeast has formed a foamy cap (if this does not happen, your yeast may be dead or your liquid was not the right temperature, you will have to start over).

Add granulated sugar, butter, egg, egg yolk, salt, nutmeg (if using) and approximately half of the flour and stir until well-combined. While stirring, gradually add additional flour until the dough clings to itself and pulls from the sides of the bowl (you can do this by hand/with a wooden spoon or using the dough hook attachment of a stand mixer). Stir (adding more flour as needed) until dough is still a bit tacky to the touch but not too sticky to be unmanageable.

If making by hand, lightly dust a clean surface with flour and knead the dough for 5-10 minutes or until smooth and elastic (add more flour as needed). If using a stand mixer, continue to mix on md/low speed until smooth/elastic, about 3-5 minutes.

Place dough in a large, lightly oiled bowl and turn so the surface is coated with a thin layer of oil. Cover tightly and place in a warm place to rise until doubled in size (about 1-2 hours). While dough is rising you can prepare your filling.

Combine brown sugar, cinnamon, allspice, nutmeg, and salt in a medium-sized bowl and whisk together until well-combined. Peel, core, and chop apples (smaller pieces are easier to roll into the cinnamon buns). If butter is not soft enough to be easily spread, pop it in the microwave for several seconds until it is nice and soft.

Lightly butter a 13×9” (33x23cm) baking dish and set aside.

Once dough has risen, gently deflate and transfer to a clean, lightly floured surface. Use a rolling pin to roll into a 10×20” (25-50cm) rectangle.

Use a knife to evenly spread butter over the surface of the dough, leaving about ½” (1.25cm) of the perimeter untouched.

Toss apples and brown sugar mixture together until apples are coated then immediately evenly sprinkle over the butter.

Starting with one of the longer edges, firmly roll dough into a log, pinching the end together to make a seam.

Use a sharp knife to immediately cut the dough into 12 even pieces and place cut-side down in prepared baking dish. You may notice a bit of the apple mixture may be oozing out of the bottom of the rolls, this is fine.

Cover rolls with a towel and place in a warm spot to rise until puffed and increased in size at least 50%, about 25-40 minutes. Meanwhile, preheat oven to 350F (175C).

Uncover risen rolls and transfer to the center rack of preheated oven. Bake 25-30 minutes (if using a metal pan, glass or ceramic may take several minutes longer) until rolls are cooked through. Once rolls have finished baking, prepare caramel glaze.

Combine brown sugar, butter, milk, and salt in a medium-sized saucepan over medium heat. Cook, stirring frequently, until butter is melted and sugar is beginning to dissolve. Bring to a full boil and boil for 5 minutes, stirring frequently.

Remove from heat and add powdered sugar and vanilla extract. Whisk until smooth.

Immediately drizzle or spread glaze over cinnamon buns (even if they are still warm). Allow glaze to set before serving.