Preheat oven to 400 degrees F.
In the stand mixer bowl, combine warm water and sugar. Stir. Sprinkle the yeast over top, give it a really quick stir then let it rest for about 5 to 10 minutes. If you're yeast is good it should be foamy after that amount of time. If not, your yeast might be bad.
Use the dough hook attachment to mix the dough. Add the flour and kosher salt to the mixer bowl slowly so it doesn't make a mess. Mix on slow speed until flour combines with the yeast mixture. Then, slowly add the extra virgin olive oil to the bowl and mix on medium-low speed for about 3 to 5 minutes. The dough should be forming a ball around the dough hook and not sticking to the sides of the bowl.
Prepare a glass mixing bowl by coating the insides with non-stick spray or oil. Then remove your dough from the mixer bowl and form into a ball. Place the ball in the prepared bowl and cover with a towel. Place in a warm spot in your kitchen and allow it to rise for 45 minutes. It should double in size. If it doesn't cover back up and allow to rise a bit longer.
Wipe the inside of a large cast iron skillet or pan with oil. Then place the dough inside and use your hands to stretch it out and press it into a round shape. You can roll it on a floured surface as well then transfer it to the pan. Personally, I like shaping it with my hands. Once it's stretched out into the pan, cover it again and allow it to rise for 15 more minutes.
Uncover the pan and use your fingertips to press dimples into the dough. You want to press deeply into the dough, you can actually press your fingertips right to the pan. Depending on how dimpled you want your focaccia you can press a little or a lot. You do you!
Drizzle half of the olive oil over top, then lay the thinly sliced apples over top. Pour the other half of the olive oil over the apples. Toss rosemary over top.
Place the pan in the oven and bake for for about 10 minutes. Open oven, remove pan and drizzle honey over the bread randomly. Place the pan bake in the oven and bake for 10 minutes more. The top should be golden brown.
Remove the pan from the oven and sprinkle with flaky salt. You can also add more olive oil or honey if desired.
Slice the focaccia and serve while it's still warm.