Olive oil is very well suited to baking. In bread, focaccia and pizza dough it gives a soft crumb and an aromatic crust. In sponge cakes it keeps the batter moist, especially together with lemon, orange or almonds.
In a dough, olive oil does not get as hot as in the pan, so it stays stable here too. A mild, fruity oil does not overpower the flavour. If you replace butter with olive oil, use about three quarters of the amount.