In a large skillet over medium heat, combine olive oil, garlic, capers, and lemon zest. Cook, stirring occasionally, until garlic is lightly golden, about 2 minutes.
Add rosé wine and simmer for 2 minutes to reduce slightly.
Stir in tomatoes, olives, and 1/4 tsp each of salt and pepper.
Nestle the cod fillets into the tomato mixture and simmer gently, covering the skillet during the last 3 minutes of cooking. Cook until the fish is opaque and flakes easily, 6 to 8 minutes total.
Sprinkle with chopped parsley and serve immediately with crusty bread or rice, if desired.