Prepare a 6-inch cast iron skillet (if you don't have cast iron, use a 6-inch round oven safe dutch oven or bowl). Using ½ tsp olive oil and a paper towel, lightly coat the entire inside of the dish to help prevent sticking.
2. Step
In a small bowl, combine warm water (about 110° F),sugar and yeast. Gently stir and set aside for 5-10 minutes. The yeast should start to bubble and foam at the top.
3. Step
In a stand mixer, combine gluten free flour, guar gum, salt, black pepper, Italian seasoning, and chopped rosemary until mixed (about 30 seconds).
4. Step
Once the yeast has become bubbly and foamy, pour into the flour mixture. Add 2 tbso olive oil. Mix on medium speed for 2-3 minutes, scraping down the sides if needed. The dough will be sticky.
5. Step
Transfer the dough to your prepared cast iron skillet. Using a spatula (get it wet to help prevent sticking),gently mound the dough into a ball, smoothing out the dough as you go. The ball should be about 4 inches in diameter.
6. Step
Using the remaining 1 tsp olive oil, gently rub it over the dough (this prevents the dough from drying out as it will not be covered during proofing. It also helps the bread develop a crispy crust.) Place the pan in a warm spot and allow the dough to double in size. This can take anywhere from 35-45 minutes, depending on the temperature. Toward the end of the dough proof, preheat your oven to 425° F (removing the pan from the oven if necessary).
7. Step
Sprinkle remaining ¼ teaspoon kosher salt on the dough. If desired, make two slashes with a sharp knife on the top (purely decorative),but be careful not to slash too deep. Place in the oven and bake for 30-35 minutes, or until the outside crust is lightly browned.
