In a mixing bowl, combine warm water, sugar, and yeast. Stir gently and let it sit for about 5-10 minutes until frothy. This activates the yeast, ensuring the dough rises properly.

Add the flour, salt, and olive oil to the yeast mixture. Mix until a shaggy dough forms.

Knead the dough on a floured surface for about 5-7 minutes until smooth and elastic. This develops the gluten, giving the bread its structure.

Place the dough in a greased bowl, cover with plastic wrap, and let it rise in a warm place for about 1 hour, or until doubled in size.

Preheat your oven to 425°F (220°C).

Once the dough has risen, punch it down to release air. Transfer it to a greased baking sheet and stretch it out to fit the sheet.

Use your fingers to create dimples in the surface of the dough. Drizzle with olive oil and sprinkle with sea salt.

Bake in the preheated oven for 20-25 minutes, or until golden brown. The bread should sound hollow when tapped on the bottom.

Remove from the oven and let it cool slightly before slicing.

Slice the focaccia horizontally to create a top and bottom for the sandwich.

Layer the fresh mozzarella, basil leaves, and tomato slices on the bottom half of the focaccia.

Drizzle with balsamic glaze and sprinkle with black pepper.

Place the top half of the focaccia on the sandwich and press down gently.

Cut into individual sandwiches and serve immediately, or wrap in parchment paper for later.