Pour the flour into a large bowl and make a well in the center. Add warm water (under 115°F so not to kill off the yeast) and sprinkle the yeast over the water. Slowly stir, mixing the flour into the water until a rough dough forms.
Add in the olive oil and salt, mixing together into a sticky dough. Turn the dough out on a very lightly floured surface.
As this dough is really sticky, use the pull and fold method until it is mostly sticking to itself instead of your hands. Simply wet your hands and pull the dough upward, folding it back over the middle. Turn the bowl a quarter turn and repeat until you’ve stretched on all sides. This takes about 5-7 minutes.
Place the dough into an oiled bowl and cover it with a damp towel or plastic wrap. You’ll want the dough to rise to double its size, which will take 60-90 minutes, depending on how warm your home is. Check it after 60 minutes.
While the dough is rising, you can prepare the focaccia toppings. Add the brown sugar and cinnamon to a small bowl and mix. Set aside 2 tablespoons of the mixture.
Melt melted coconut oil and add to the remaining sugar mixture, stirring into a paste.
Prepare a 9”x13” pan with 2 tablespoons of olive oil, spreading it out, so it’s even. Place the dough in the pan, stretching it out to the corners using your fingers.
Spread about half of the cinnamon sugar paste on top of the dough. Fold the dough in half, stretching it to the edges of the pan again.
Add the remaining cinnamon sugar mixture on top.
Cover the dough again and allow it to rise until it’s about one and a half times the original size. This should take 30-60 minutes. While the focaccia is rising, heat the oven to 425°F.
Dip your fingers in oil and use them to push lots of dimples into the focaccia dough. Sprinkle on the cinnamon sugar you set aside.
Bake the sweet focaccia for 20-22 minutes until the top is golden brown and very firm to the touch.. Allow it to cool in the pan for about 10 minutes.
Add powdered sugar, vanilla, and oat milk to a bowl and stir until a smooth, pourable icing forms.
Pour the vanilla icing over the focaccia. Allow it to cool for at least another 20 minutes or so before you cut and serve it. If you have time to cool it completely, it will keep the insides more moist, as cutting it will allow moisture to escape.
This Sweet Focaccia is really best the same day, but it can be stored for up to 3 days in an airtight container in the refrigerator.