Ingredients (below makes 1 baguette. double everything to make two)
250g White Bread Flour
0.5g Active Dry Yeast (1/8th teaspoon)
Mix all the ingredients together until it forms a lump. I use a stand mixer because it reduces mess, but you could use your hands.
Leave lump covered in a bowl at room temperature for around 12 hours (anywhere between 8-18 hours is fine).
Shape lump into baguette shape (dust chopping board with flour and scrape dough mixture out onto it. then pull left side and fold right back over itself like you're pulling out the sleeves and folding them back on top of a shirt. repeat on other side; pull right side and fold over left. then take end nearest you and fold it onto itself in a rolling manner away from you. then roll, roll, roll until you get a long sausage shape).
Place baguette onto baking tray (i use non-stick baking paper on the tray but you could just flour the tray if you're feeling lucky). Let prove for 1 final hour (i set an additional timer to 40 mins so i know when to turn the oven on).
Pre-heat oven to 250ºC. Place empty metal cooking tray in bottom of oven to pre-heat. Put the kettle on to boil around 500-1000ml of water.
Score baguette (the lines need to overlap or you get a lumpy baguette).
You need to do the next bit quite quickly and efficiently: Place tray with baguette in middle of oven then pour boiling water from kettle into the metal cooking tray that was pre-heating at the bottom of the oven. Shut the oven door quickly to keep as much steam in as possible.
Bake baguette for around 15 mins total. After first 10 mins remove and turn the tray with baguette around so both sides of baguette cook evenly.
Remove from oven and place baguette onto cooling rack. Wait about 20-30 mins to cool before cutting open.
Thats it! enjoy!
edit: if you want to use Shipton Mill's French Type 55 White Flour (which makes a very lovely, light, and slightly sweet baguette) then you will need to reduce the cooking time a little bit (12-13 mins total). you can also increase hydration up to 70% (so 175g water for 250g flour, or 350g water for 500g flour).