Add the warm water, yeast and sugar to a mixing bowl. Let it sit for two minutes. Add ¼ cup of the oil.

In a second bowl, mix together the flour, salt and sugar.

Add the dry ingredients to the water mixture and stir for about 20 seconds to combine. The dough will form a ball but it will be quite sticky.

Cover with a clean kitchen towel or plastic wrap and allow the dough to rest and rise for 15 minutes.

Stretch and fold the dough. Use wet hands and grab the dough on one side, pulling it upwards and fold it down towards the opposite side. Turn the bowl a quarter turn and pull and fold again. Repeat this about 10 times. The dough will tighten up a bit. Again, cover the dough and set it aside to rest for another 15 minutes. Repeat the stretch and fold a second time, cover and rest for another 15 minutes.

Add two tablespoons of the remaining oil, along with the melted butter to a 9x13-inch, non-stick baking pan. Use a pastry brush to ensure the entire pan, including its sides are coated. Place the dough in the pan and push it into the edges and sides of the pan as much as possible. Cover again and let rest for 1 hour.

Meanwhile, preheat the oven to 400°F

Drizzle the remaining two tablespoons of oil over the focaccia dough. Dimple the dough with your fingertips.

Place the focaccia on the middle rack of the oven and bake for 30-35 minutes or until golden brown and crispy around the edges and cooked through. Remove the pan from the oven. Cool for 10 minutes.

Transfer the cooked focaccia to a cutting board. Cool completely.

Mix together the lemon juice and icing sugar

Pipe the jam into the focaccia and drizzle with the lemon glaze