Introduction

This Onion Boil with Crab is a comforting, flavorful seafood feast perfect for sharing with family and friends. Combining sweet onions, tender potatoes, corn, and succulent crab legs, it’s a simple one-pot meal that captures the essence of a coastal boil.

A large white pot filled with a layered seafood dish shows bright orange crab legs on top, covered with light seasoning and small green herbs. Below the crab legs, there are yellow corn pieces cut into chunks, tender-looking red and white potatoes cut in halves and quarters, and slices of lemon adding a fresh yellow color. The ingredients are mixed and sprinkled with green dill, creating a colorful, textured seafood boil. The pot sits on a white marbled surface, glowing warmly in natural light. photo taken with an iphone --ar 4:5 --v 7

Ingredients

2 pounds crab legs
4 large yellow onions, peeled and quartered
1.5 pounds red potatoes, halved
4 ears corn on the cob, halved
1 garlic bulb, halved crosswise
2 lemons, sliced
3 bay leaves
3 tablespoons Old Bay seasoning
1 tablespoon salt
1 teaspoon black peppercorns
1/2 cup unsalted butter
10 cups water

Instructions

Step 1: Place a large stockpot over medium-high heat.
Step 2: Add water, onions, garlic, lemon slices, bay leaves, Old Bay seasoning, salt, and black peppercorns to the pot. Bring to a boil.
Step 3: Simmer for 15–20 minutes to infuse flavor from the onions and aromatics.
Step 4: Add the potatoes and cook for 10 minutes. Then add the corn and cook for another 5 minutes.
Step 5: Add crab legs and cook for 6–8 minutes until heated through.
Step 6: Turn off the heat, stir in the butter, and let the pot rest for 5 minutes.
Step 7: Use tongs or a slotted spoon to serve crab, onions, and veggies onto a tray. Ladle broth over top if desired.

Tips & Variations

For an extra kick, add a pinch of cayenne pepper or hot sauce to the broth.
Swap red potatoes for fingerlings or Yukon golds if preferred.
Add smoked sausage slices for a heartier meal.
Use fresh crab or substitute with shrimp or lobster tails depending on availability.

Storage

Store leftovers in an airtight container in the refrigerator for up to 2 days. Reheat gently in a covered pot over low heat, adding a splash of water or broth to keep everything moist.

How to Serve

A large metal tray is filled with a mix of seafood and vegetables soaked in a seasoned sauce. The dish has bright orange crab legs and claws spread across the tray, with plump pink shrimp scattered between them. Yellow corn on the cob chunks and small whole potatoes in both yellow and red tones are mixed evenly throughout. Lemon wedges with a pale yellow color are placed on top and along the edges. The whole dish is sprinkled with chopped green herbs, adding texture and color contrast. The tray sits on a white marbled surface with a brown cloth visible in the corner. photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I use frozen crab legs for this recipe?

Yes, frozen crab legs work well—just thaw them before adding to the pot and adjust the cooking time slightly if needed.

Is there a way to make this recipe spicier?

Absolutely. You can add cayenne pepper, red pepper flakes, or a few dashes of hot sauce to the broth to increase the heat to your preference.

Onion Boil with Crab Recipe

Print Recipe

★★★★★

4.7 from 507 reviews

A classic seafood boil featuring tender crab legs, sweet corn, and hearty potatoes simmered with aromatic onions and Old Bay seasoning for a flavorful, comforting meal.

Author: Marco
Prep Time: 15 minutes
Cook Time: 40 minutes
Total Time: 55 minutes
Yield: 4 servings 1x
Category: Seafood Boil
Method: Stovetop
Cuisine: American

Ingredients

Scale

Seafood and Vegetables

2 pounds crab legs
4 large yellow onions, peeled and quartered
1.5 pounds red potatoes, halved
4 ears corn on the cob, halved
1 garlic bulb, halved crosswise
2 lemons, sliced

Seasonings and Other

3 bay leaves
3 tablespoons Old Bay seasoning
1 tablespoon salt
1 teaspoon black peppercorns
1/2 cup unsalted butter
10 cups water

Instructions

Prepare the stockpot: Place a large stockpot over medium-high heat to get it ready for boiling.
Add aromatics and seasonings: Pour in the water along with onions, garlic, lemon slices, bay leaves, Old Bay seasoning, salt, and black peppercorns. Bring this mixture to a rolling boil to develop the base flavors.
Simmer the broth: Reduce the heat slightly and simmer for 15–20 minutes. This allows the aromatics to infuse their flavors fully into the water.
Cook the potatoes: Add the halved red potatoes to the pot and cook for 10 minutes, allowing them to soften.
Add corn and continue cooking: Introduce the halved corn ears to the pot and cook for an additional 5 minutes, ensuring they become tender.
Cook crab legs: Add the crab legs and cook for 6–8 minutes until they are heated through and flavors meld.
Finish with butter and rest: Turn off the heat, stir in the unsalted butter to add richness, and let the pot rest for 5 minutes to allow flavors to settle.
Serve: Use tongs or a slotted spoon to transfer the crab, onions, potatoes, and corn onto a serving tray. Ladle some of the flavorful broth over the top if desired before serving.

Notes

Use fresh or frozen crab legs; if frozen, thaw before cooking for even heating.
Feel free to adjust Old Bay seasoning amount based on your spice preference.
Butter adds richness but can be omitted or substituted with olive oil for a lighter version.
Serve with crusty bread or additional lemon wedges for added flavor.
Be cautious of shell fragments while eating crab legs.

Keywords: crab boil, seafood boil, crab legs, Old Bay seasoning, onion boil, corn on the cob, red potatoes, seafood recipe