Preheat oven to 200℃ (180℃ fan forced). Grab a small sheet of foil and place the garlic onto the foil, cut side up. Drizzle with oil then bunch the foil up and around the garlic to enclose. Bake for 30-40 minutes or until very soft and lightly golden. Remove and allow to cool.
Meanwhile, melt the butter in a saucepan (SEE NOTE 3) over medium heat until foamy. Once foaming, stir often until it starts to turn brown, but be careful to not let it burn. It can happen quite quickly. Once browned, immediately pour into a small bowl. Set aside to cool.
Once butter has cooled (but not hard), squeeze the garlic out from the skins and add to the butter. Using a whisk, whisk for around 2-3 minutes or until creamy. Add the parsley and salt and stir to combine.
Preheat the oven to 220℃ (200℃ fan forced). Slice the bread into 1cm thick slices but do not cut all the way through. Slather all the cut slices of bread with the brown butter mixture then wrap the bread in a sheet of foil to enclose at the top. Place onto a baking tray and pop into the oven. Bake for 15 minutes.
Open up the foil to expose the bread and return to the oven for a further 3-5 minutes to get golden brown. Remove and stand for 5 minutes before serving.