In a small bowl, combine 2 teaspoons of active dry yeast, 2 teaspoons of honey, and 2 cups of lukewarm water. Stir gently and let it sit for about 5-10 minutes, or until it becomes frothy.
In a large mixing bowl, combine 5 cups of all-purpose flour and 5 teaspoons of kosher salt. Make a well in the center and pour in the activated yeast mixture. Using a wooden spoon, mix until the dough begins to come together.
Transfer the dough onto a lightly floured surface and knead for about 8-10 minutes, or until the dough is smooth and elastic.
Grease a large bowl with unsalted butter and place the dough inside, turning it to coat with the butter. Cover the bowl with plastic wrap and let it rise in a warm place for about 1 to 2 hours, or until it has doubled in size.
Once the dough has risen, punch it down to release the air. Grease your 9x13 inch baking pan with olive oil. Transfer the dough to the pan and gently stretch it to fit. Use your fingers to create dimples all over the surface of the dough.
Arrange your sliced garden vegetables on top of the focaccia in an artistic manner. Drizzle with additional olive oil and sprinkle with flaky sea salt.
Cover the pan with a kitchen towel and let it rise for another 30-45 minutes.
Preheat your oven to 425°F (220°C). Bake the focaccia for 20-25 minutes or until it is golden brown and sounds hollow when tapped.
Once baked, remove the focaccia from the oven and let it cool in the pan for about 10 minutes. Transfer to a wire rack to cool completely. Slice and serve warm or at room temperature.
