Feeding the Sourdough StarterTake 25 grams of leftover sourdough starter out of the fridge. Feed your starter 50 grams of water and 50 grams of bread flour. Mix the flour, water, and starter around in the jar until it has a pancake batter-like consistency. Mark the top of the starter with a rubber band and cover the top loosely with a lid. Let the starter rise at room temperature overnight, for around 6-8 hours, or until it doubles in size.

Mixing the DoughPlace a mixing bowl on a digital scale and weigh in the water, milk, sourdough starter, melted butter, white sugar, and salt. Stir the liquid ingredients together until well combined. Then, add the bread flour. Mix the ingredients together with a spoon until a rough dough is formed and most of the dry bits of flour disappear. Then cover up the dough with a kitchen towel and let it rest for 10 minutes. After the ten minute rest the dough will be easier to knead.

Kneading the DoughUncover the dough and dump it out onto the un-floured kitchen counter. Knead the dough by hand for about eight minutes, or until the dough is smooth and holds together will. Form the dough into a ball on the counter.

The First Rise (Bulk Fermentation)Move the dough into a large glass bowl with a lid (or any other mixing bowl). Grease the bowl first with a small amount of butter or olive oil first so that the dough doesn’t stick. Cover the bowl with the lid or a sheet of plastic wrap and let the dough rise at room temperature for 4-6 hours, or until it roughly doubles in size.

ShapingAfter the dough has doubled in size, remove it from the bowl and place it onto the kitchen counter. Gently preshape the dough into a tight ball. This will knock some of the air out of the dough and make the dough easier to shape into a loaf-pan-shape later. Let the ball of dough rest, uncovered, for 15 minutes.

While the dough is resting, prepare a standard, non-stick bread pan by greasing it with a bit of butter or oil (this part is optional if the bread pan is non-stick).

After the 15 minute rest, shape the dough to fit the bread pan. Flip the ball of dough over so that the sticky side is now facing up. Fold the dough together like a book, then give the dough a 90° turn, and fold the ends of the dough together like a book again. Pinch the seams of the dough together so that the seams close, then flip the dough over and you should have an oval loaf of dough that fits nicely in your bread pan. Transfer the dough into the greased bread pan and cover the pan with a kitchen towel.

The Second Rise (Final Proof)Let the covered dough rise on the kitchen counter at room temperature for 2-4 hours, or until the dough is doubled in size. Since you won’t be scoring this loaf, you can let the dough proof longer to reach its full potential before baking it. (Sandwich breads that don’t proof for a long enough time tend to rip along the sides of the loaf when they’re baking in the oven).

In my warm Arizona kitchen, my dough took just two and a half hours to proof before it doubled in size. Yours may take a little bit longer, so be patient in the final proof.

Baking30 minutes before the dough is done proofing, preheat your oven to 400°F (204°C). Place a metal pie pan or cake pan on the bottom rack of the oven. This will heat up and you can use it as a steam tray.

When the oven is preheated and the dough is proofed, beat one small egg and brush the beaten egg over the top of the dough with a pastry brush. This egg wash will give the bread a shiny, golden-brown top.Slide the bread into the middle rack of the oven and pour one cup of boiling water into the metal cake pan below. This will create steam while the bread bakes, allowing it to rise properly.

Bake the bread for 20 minutes with the steam and then carefully remove the metal steam tray. Continue baking for another 20 minutes without steam.

After baking, remove the bread from the pan and allow it to cool for at least one hour on a cooling rack.

Slice the bread and enjoy it on its own, as slices for buttered toast, or as the perfect sliced bread for BLTs. The lightly sweet and tangy flavor of this bread make it the perfect, homemade, easy sourdough sandwich bread.