Heat 2 tablespoons oil in heavy medium saucepan over medium-high heat. Add onion and garlic; sauté until tender, about 5 minutes. Add apple juice, red wine, vinegar, rosemary, thyme and crushed red pepper; bring to boil. Reduce heat; simmer until mixture is reduced to 1 1/2 cups, stirring occasionally, about 20 minutes. Strain mixture into small saucepan; discard solids. Add cream and simmer until reduced to sauce consistency, about 12 minutes.
Meanwhile heat 2 teaspoons oil in heavy medium skillet over medium heat. Add pear slices; sauté until tender and golden brown, about 8 minutes. (Sauce and pears can be prepared 2 hours ahead. Cover separately and refrigerate. Rewarm pears over medium-low heat before serving.)
Heat remaining 1 tablespoon oil in heavy large skillet over medium-high heat. Sprinkle chicken with salt and pepper. Add to skillet and sauté until cooked through and golden brown on both sides, about 4 minutes per side. Add Marsala and bring to boil. Stir in reserved sauce, turning chicken once to coat. Cook until heated through, about 2 minutes longer.
Divide chicken among 4 plates. Spoons some sauce around chicken on each plate. Garnish with pear slices.
