Preheat oven to 400 Degrees. In a large bowl combine flour, brown sugar, baking soda and salt and set aside. In a separate bowl combine the buttermilk, 1 Tblsp of the finely minced rosemary, molasses, and steel cut oats and ALLOW THE MIXTURE TO SIT FOR AT LEAST 15-20 MINUTES to soften the oats. After oats have softened, make a well in the dry ingredients and pour in the liquid mixture. Stir with a wooden spoon just until combined. (Do NOT overmix or bread will be tough.) Next, stir in the raisins. Scoop the dough onto a floured surface and dust with flour. Knead slightly to form the dough into a ball. Spray an 8 or 9 inch cast iron skillet with cooking spray. Use your bench scraper to lift and move dough into the cast iron skillet. Cut an X into the bread about 1/3 of the way down through the loaf. Brush the top with melted butter and sprinkle the remaining Tblsp. of rosemary over the top of the loaf. Bake at 400 degrees for approximately 40 minutes or until bread sounds "hollow" when tapped. Allow to cool slightly before slicing. ENJOY!