Blackstone Grouper (Pan-Seared on the Flat Top)

Name: Blackstone Grouper
Prep time: 5 min
Cook time: 10 min
Total time: 15 min
Yield: 4 servings
Cuisine: American
Ingredients: 4 grouper fillets (6–8 oz each, 1 inch thick); 2 tbsp olive oil; 2 tbsp butter; 3 cloves garlic, minced; 1 tsp Old Bay or Cajun seasoning; Salt and pepper; 1 lemon

Grouper is one of the meatiest, most satisfying white fish you can put on a Blackstone. It has a firm texture that holds together on the griddle without falling apart, a mild-sweet flavor that pairs well with bold seasonings, and thick fillets that develop an excellent sear without drying out. The flat-top is particularly suited to grouper because the fish stays flat under direct heat — no curling, no uneven cooking.

Prep time: 5 minutes · Cook time: 10 minutes · Serves: 4

Griddle temperature: 375–400°F (medium-high heat)

Ingredients

4 grouper fillets (6–8 oz each, 1 inch thick)
2 tbsp olive oil or avocado oil
2 tbsp butter
3 cloves garlic, minced
1 tsp Old Bay seasoning or Cajun seasoning
½ tsp salt
½ tsp black pepper
1 lemon, cut into wedges
Fresh parsley or cilantro to garnish

Instructions

Step 1: Season the grouper

Pat fillets dry. Drizzle with olive oil and season both sides with Old Bay (or Cajun seasoning), salt, and pepper.

Step 2: Preheat the griddle

Bring to medium-high (375–400°F). Add butter and olive oil to the cooking surface. Let butter melt and foam.

Step 3: Add garlic

Add minced garlic to the butter zone. Sauté 30 seconds until fragrant — don’t let it brown. Spread the garlic butter across the cooking area.

Step 4: Sear first side

Place grouper fillets in the garlic butter. Cook without moving for 4–5 minutes until the bottom is golden brown. The fish will release from the steel when the crust has formed.

Step 5: Flip and finish

Flip carefully. Spoon the garlic butter from the griddle over the top of the fish (basting). Cook 3–4 more minutes until opaque throughout and reads 145°F internal temperature.

Step 6: Serve

Squeeze lemon over the top, garnish with parsley or cilantro, and serve immediately.

Tips

Grouper holds together well. It’s one of the best fish for beginners on the flat top — firm enough that you don’t need to worry about it falling apart when you flip.

Cajun or Old Bay works great. Grouper’s mild sweetness handles bold spice profiles well. Try blackened grouper — generous Cajun seasoning at 400°F gives you a dark, spicy crust without the need for a cast-iron pan.

Baste while it cooks. Spooning the garlic butter over the fish as it cooks on the second side keeps it moist and adds the garlic flavor through the flesh rather than just on the exterior.

Serve immediately. Fish deteriorates quickly off heat. Have your sides ready before the grouper hits the griddle.

More flat-top recipes: Blackstone Fish Recipes · Blackstone Dinner Ideas

Frequently Asked Questions

What temperature do you cook grouper on a Blackstone griddle?

375–400°F — medium-high heat. Grouper is a thick, meaty fish that can handle the heat. The internal target is 145°F. At 375–400°F, 1-inch-thick grouper fillets reach the right temperature in about 10 minutes.

How long does grouper take on a Blackstone?

4–5 minutes per side for 1-inch fillets — about 10 minutes total. Larger 1½-inch fillets may need 12–14 minutes. The fish is done when opaque throughout and flakes easily at 145°F internal temperature.

What seasoning is best for grouper on the Blackstone?

Old Bay and Cajun seasoning are the most popular choices. Grouper’s mild, slightly sweet flavor handles bold spice well. For blackened grouper, use a generous amount of Cajun seasoning (cumin, paprika, cayenne, garlic, onion) and cook at 400°F.