Stir the flour, turmeric, salt and yeast together in a large mixing bowl.
Make a well in the centre and add the olive oil and water (note: the water doesn't have to be a particular temperature - just tepid/lukewarm). Mix to form a loose dough.
Tip the dough onto a lightly floured counter (note: if your counter is wooden or porous, protect it from the turmeric staining with a piece of plastic wrap/clingfilm).
Knead the dough for 10 mins or until smooth. You can also do this in a stand mixer with a dough hook.
Place the dough into a lightly oiled mixing bowl and cover with a clean tea towel. Leave to rise on the counter for 1 hour or until doubled in size. Note: you can also place in the fridge overnight to slowly rise.
Lightly oil a baking tray or cookie sheet. Knock back the dough by punching the air out and folding the dough over itself. Form it into a ball, then place it on the cookie sheet for 1 hour or until doubled in size.
Heat oven to 430F / 220C.
Dust the loaf with a little flour and cut a cross about in the top of the loaf.
Bake for 25-30 mins until golden brown and the loaf sounds hollow when tapped underneath. Allow to cool on a wire rack before cutting.
4 cups (500g) strong white bread flour plus extra for dusting
2 tsp salt
½ tsp turmeric powder
2 ¼ tsp (7g sachet) fast-action yeast
3 tbsp olive oil
1 ⅓ cups (300ml) tepid water
For the spirulina avocado (per serving)
½ avocado mashed
¼ tsp spirulina
toppings such as chilli flakes, seeds, herbs