Place the flour into a large bowl and rub in the yeast.
Add the basil, oil, salt and water and mix to form a dough (adding more water if it feels a little dry).
Place the dough onto a lightly oiled surface and knead for around 10 minutes, or until it feels smooth and elastic.
Return the dough to the bowl and cover with a tea towel.
Leave the dough to rise, for around an hour, or until it has doubled in size.
When the dough has risen, place it into a lightly greased 20cm cake tin, gently pushing it into the sides so it fills the tin.
Cover again with a tea towel and leave to rise for 30 minutes, or until it has noticeably puffed up.
Pre-heat the oven to 200 degrees c.
When the focaccia has risen, make indents all over the surface with your knuckles and sprinkle over the basil, tomato, cheese and salt.
Drizzle over the oil and place the cake tin onto a baking tray (incase the cheese spills over).
Bake for around 20 minutes, or until the cheese is deliciously burnished and cool a little in the tin before serving.
Little tip: Different flours will absorb different amounts of liquid, so I would add ¾ of the suggested liquid to the mixture at first and then if the dough feels a little dry, you can always add some more.