In the bowl of a stand mixer, combine yeast, water and honey. Stir well and let it stand for 10 minutes.
In a large bowl, whisk together flour, ground rosemary and salt; set aside.
Add olive oil and flour mixture to yeast and using the dough hook attachment, process on speed 4 for 6 to 7 minutes or until it forms a ball, adding more flour if necessary.
Remove dough and shape into a ball by pulling it under. Place dough in a lightly oiled bowl and swirl to coat. Cover with plastic wrap then a dish towel before transfering to a draft-free area such as the oven (temperature off) for 1 ½ to 2 hours or until it doubles its size.
Punch dough to deflate it and then oil the same plastic wrap used earlier; cover and let it sit for 15 minutes.
Grease a 9x13-inch cookie sheet with oil; set aside.
Place the dough on the prepared cookie sheet and roll into a rectangular shape – if the dough starts shrinking, stop and wait 5 minutes for the gluten to relax before continuing to shape it.
Cover with a dish towel and let it proof until it doubles in size, about 30 minutes.
Preheat oven to 425ºF.
When time is up, with the fingertips, make dimples on top of the dough. Place sliced tomatoes on top of the focaccia; sprinkle with coarse sea salt, freshly ground black pepper, and rosemary.
Drizzle the remaining olive oil over the bread before transferring to the preheated oven. Bake for 25 to 30 minutes or until the focaccia is golden brown
Remove from the heat and let it rest for 10 minutes before serving (*see foonote).