The rosemary steeps in boiling water; be sure to let it cool to 100° to 110° before adding the yeast so your dough will rise correctly. Sea salt and kosher salt have larger crystals than regular salt, so either adds a nice crunch to the top of the focaccia bread. But be sure to use regular salt in the dough for best results. You don't need to use all of the egg and oil mixture on top of the dough; spread enough to coat the top, and discard any extra. Use remaining bread for sandwiches, or cut into 1/2-inch cubes and bake at 350° for 15 minutes (or until toasted) to make croutons for salads.
1 1/4 cups boiling water
3 tablespoons chopped fresh rosemary, divided
1 tablespoon honey
1 package dry yeast (about 2 1/4 teaspoons)
3 3/4 cups all-purpose flour, divided
1/4 cup olive oil, divided
1 teaspoon salt
1 teaspoon water
1 large egg yolk
1 teaspoon sea salt or kosher salt
How to Make It
Combine boiling water, 1 teaspoon rosemary, and honey in a large bowl; cool to 100° to 110°. Sprinkle yeast over honey mixture; let stand 5 minutes. Lightly spoon flour into dry measuring cups; level with a knife. Add 3 1/4 cups flour, 2 tablespoons oil, and 1 teaspoon salt to honey mixture, stirring to form a soft dough. Turn dough out onto a floured surface. Knead until smooth and elastic (about 10 minutes); add enough of remaining flour, 1 tablespoon at a time, to prevent dough from sticking to hands (dough will feel sticky).
Place dough in a large bowl coated with cooking spray, turning to coat top. Cover and let rise in a warm place (85°), free from drafts, 45 minutes or until doubled in size. (Gently press two fingers into dough. If indentation remains, dough has risen enough.) Punch dough down. Pat dough into a 14 x 12-inch rectangle on a baking sheet coated with cooking spray. Cover and let rise 20 minutes or until doubled in size.
Preheat oven to 350º.
Uncover dough. Make indentations in top of dough using handle of a wooden spoon or your fingertips. Combine 1 tablespoon oil, 1 teaspoon water, and egg yolk; brush over dough. Drizzle with remaining 1 tablespoon oil; sprinkle with remaining rosemary and sea salt.
Bake at 350° for 25 minutes or until lightly browned. Remove from pan; cool on a wire rack.