Preheat your oven to 200 F / 95 C. In a large bowl or the bowl of a stand mixer, combine 4 1/4 cups flour, 4 1/2 tsp or 2 packets of instant dry yeast, 1 Tbsp + 1 Tsp poppy seeds, and 1 tsp salt.

In a separate bowl, combine 1 cup buttermilk, 1/2 cup granulated sugar, and 1/2 cup butter (cut into Tbsp-sized pieces). Heat for 1 minute in the microwave, then stir to combine the ingredients. The butter should be mostly melted, and the mixture should feel warm but not hot to the touch. If it's too hot, it can kill the yeast!

Slowly pour the warm buttermilk mixture into the dry ingredients and mix on medium speed with a dough hook or by hand with a dough whisk. If you don't have a dough whisk, you can use a large wooden spoon. The dough should be quite sticky at this point.

Mix in 2 large eggs, one at a time, on a medium-low speed until a sticky dough ball forms. It will take a while for each egg to get incorporated, but keep mixing until they are fully combined. Then continue to mix on a medium-low speed for a couple of minutes until the dough becomes more elastic. Once combined, mix in the zest of 2 large lemons on a medium speed until incorporated.

As the dough mixes, add additional flour 1 Tbsp at a time until the dough begins to leave the sides of the bowl. I usually add about 3 additional Tbsps of flour. My favorite way to know if my dough is ready is to poke it with my finger. It should feel tacky but not sticky. As you pull your finger away, there should be no residue on your finger.

Cover the bowl with plastic wrap or a towel and set aside to let the dough rest for 10-20 minutes. This will make it easier to roll out.

As the dough rests, make the lemon roll filling. In a medium-sized bowl, add 1/2 cup granulated sugar, 1/2 cup light brown sugar, and the zest of 2 large lemons. Massage the zest into the sugar with your fingertips to help release the oil from the zest. The mixture should be aromatic as you do this.

Add 1/2 cup softened butter (the butter should be soft to the touch, and almost a bit melted) to the mixture. Whisk until combined, then set aside.

Once the dough has rested, place it on a lightly floured surface and roll it into a large rectangle that's roughly 12 in x 18 in. It should be about 1/2 cm thick.

Spread the lemon roll filling over the dough, leaving 1/2 inch of dough on the long side of the rectangle uncovered (this will help you seal off the roll and keep it tight).

Then roll the dough horizontally, toward the uncovered strip and cut 12 equal pieces using dental floss. Place the rolls in a greased or lined 9x13-inch pan.

Turn the oven off! I REPEAT, TURN THE OVEN OFF. Then cover the lemon rolls with foil and place them in the oven for about 30 minutes to give them an assisted rise. They should look puffier and have grown in size once they've risen.

Remove them from the oven and take off the tinfoil. Turn the oven back on and heat it to 350 F / 175 C.

Once the oven is preheated, bake the lemon rolls for 28-32 minutes or until the rolls are golden brown.

The last step is to make the icing! Whisk 2 cups of powdered sugar, 1/4 cup of fresh lemon juice, and 2 Tbsp melted butter until combined.

Let the rolls cool for 10-20 minutes, then spoon the icing over the rolls and top with fresh lemon zest.