Combine broth and porcini mushrooms in a small microwave-safe bowl. Cover with wax paper; microwave at high 2 minutes; let stand 10 minutes.
Heat oil in a large nonstick skillet over medium-high heat. Add button mushrooms, rosemary, salt, and garlic; sauté 3 minutes. Add broth mixture and porcini mushrooms to pan; remove from heat.
Bring water to a boil in a large stockpot. Add ziti; return to a boil. Cook, uncovered, 10 minutes or until al dente, stirring occasionally. Drain. Stir ziti into mushroom mixture; cook 3 minutes or until thoroughly heated. Stir in cheese, parsley, and pepper.