Step 1

Premix & Autolyse:Add your sourdough starter, flour and water into your stand mixer or Thermomix. Mix the ingredients for around 30 seconds until they are just combined into a shaggy dough. Leave to autolyse for around 30 minutes.Thermomix - dough mode 30 seconds.

Step 2

Now add the rest of your ingredients - salt, butter, sugar, (and milk powder if you're using it). Mix the ingredients for around 1 minute or until they are combined together. Now leave to rest for around 30 minutes.Thermomix - dough mode for 1 minute.

Step 3

Kneading Your Sandwich Dough:Using your stand mixer or Thermomix, knead the dough for around 3 minutes. If you are using a stand mixer, you'll need to use your dough hook. The dough should become very elastic. You won't be able to see the butter as it will be well combined into the dough. If the dough is getting a little warm from being mixed in the mixer, give it a 10 minute rest. If it seems ok, knead for the full 3 minutes. Now give your dough a 30 minute rest.Thermomix - dough mode for 3 minutes.

Step 4

Knead your dough in the mixer for another 2-3 minutes. You'll know it's ready when it is slapping the sides of the bowl of your Thermomix or Stand Mixer. The dough will be very elastic and quite silky and smooth. It shouldn't be sticking to the sides of the bowl at all. If it's not quite there, it's ok to knead for a few more minutes to develop the gluten and get it to where it needs to be.

Step 5

Bulk Ferment:Once your dough is kneaded sufficiently, you need to bulk ferment it. If you're using a stand mixer, it's fine to leave it in the mixing bowl. If you're using a Thermomix you'll need to tip your dough into a glass or ceramic bowl to finish its bulk ferment. At this point, you can just leave the dough as it is, covering it with some plastic wrap to stop it drying out. If you prefer your dough to be a bit neater, you can wet your hands and fold it into a neat ball.As with any sourdough bread, the bulk ferment time will depend on the temperature in your kitchen and of course the strength of your starter. You're looking for your dough to be just UNDER double.

Step 6

Shaping:Once your dough has finished its bulk ferment you can shape your dough. Before you start shaping, lightly butter your loaf tin.Ease your dough out of the bowl using a silicone dough scraper, remembering to have the smooth side on the counter and the sticky side facing up. You shouldn't need any flour for this as your dough shouldn't stick (it's such a beautiful silky, enriched dough).Gently ease your dough out into a rough rectangle, with the shortest side in front of you.Pop any large bubbles and gently flatten the dough using your fingertips. Then roll the dough up into a log (using the short side) and tuck the ends under. Leave the dough to sit and relax for around 30 minutes. After 30 minutes, tighten up the log by pulling the dough a little, using the sticky underside to create tension. Then simply plop the log into your buttered tin.

Step 7

Second Rise:Once your bread has been shaped and is in the tin, you'll need to let it rise again so that it fills up the shape of the tin. This should only take a few hours, but like the bulk ferment, this will depend on the strength of your starter and the temperature of your kitchen. You'll know it's done when it's risen above the lip of the tin (if you're using an open tin). It will be rounded on the top. When you poke it it will leave a slight indent but spring back nice and slowly. If you shaped it quite tight, you'll see some tension on the top of the dough as it's risen.

Step 8

Baking Your Sandwich Bread:Preheat your oven to around 180C/350F. Let your oven warm for around 10 minutes and then place your sandwich loaf in the oven and bake for approximately 40 minutes or until the top is golden brown. It may take a little longer depending on your oven. Once the loaf is baked, carefully place it on a rack to cool. Try to leave it at least one hour before you slice into it. If you have used milk powder in your dough, just watch the top of your loaf - if it's starting to burn, cover it in foil for the remainder of the bake.

Step 9

Once your dough is baked, remove it from the tin and leave to cool on a wire rack. Ideally, leave it for at least 90 minutes before you cut into it. Enjoy!