Onion Boil in Foil

Name: Onion Boil in Foil with Cajun Butter
Prep time: 5 min
Cook time: 45 min
Total time: 50 min
Yield: 3 servings
Cuisine: American
Ingredients: 1/4 cup butter, melted; 1 tbsp Cajun spice blend; 1 tsp smoked paprika; 1 tbsp garlic, minced; salt, to taste; 3 yellow onions; 1 tsp olive oil; lemon juice, for serving

This onion boil features yellow onions wrapped in foil and steamed in a flavorful Cajun butter sauce with smoked paprika and garlic, creating tender, caramelized vegetables that work as either a side dish or standalone snack.

🌍American 🏷️Onion boil 🏷️Roasted onions 🏷️Cajun 🏷️Spicy Savory

🏷️

🏷️Side dish

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TikTok

Total

50 min

Servings

3

Difficulty

Easy

Est. Cost

$17–$28

Recipe Source

View original recipe

From TikTok

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TikTok

Ingredients

1/4 cup butter, melted
1 tbsp Cajun spice blend
1 tsp smoked paprika
1 tbsp garlic, minced
salt, to taste
3 yellow onions
1 tsp olive oil
lemon juice, for servingoptional

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Instructions

1
In a small bowl, combine the melted butter, Cajun spice blend, smoked paprika, minced garlic, and salt. Mix until well combined.
2
Peel the onions and trim off the root end.
3
Slice the onion downwards into wedges, but do not cut all the way through the bottom, so the onion holds its shape.
4
Place each onion on a large piece of aluminum foil.
5
Spoon the Cajun butter mixture over and into the crevices of each onion.
6
Drizzle a little olive oil over each onion.
7
Wrap each onion tightly in its foil packet.
8
Place the foil packets in the air fryer basket and cook for 45 minutes.
9
Carefully unwrap the onions, transfer to a serving plate, and squeeze fresh lemon juice over the top before serving.

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Tips & Notes

Pro tips

Cut onions into thick wedges or halves to prevent them from breaking apart during cooking; they'll soften without falling to pieces.
Melt butter and mix spices before pouring over onions to ensure even seasoning distribution throughout the foil packet.
Don't skip the smoked paprika—it adds depth and authentic Cajun flavor that regular paprika cannot match.
Squeeze fresh lemon juice over the cooked onions just before serving to brighten the savory, buttery sauce.

Substitutions

Butter → ghee or avocado oil (dairy-free; use same amount for richness)
Yellow onions → white or sweet onions (white cooks slightly faster; sweet adds mildness)
Cajun spice blend → Old Bay seasoning or Creole seasoning (adjust to taste; some blends are saltier)

Storage & make-ahead

Store leftovers in an airtight container in the refrigerator for up to 3 days; reheat gently in foil over medium heat or in a skillet with a little water.

Equipment

aluminum foil · grill or oven

Common Questions

Can I prepare this ahead of time?

Yes, assemble the foil packets with onions and butter sauce up to 4 hours ahead, then refrigerate. Cook when ready—add 2–3 minutes to cooking time if starting from cold.

How do I know when the onions are done?

Pierce the foil with a fork or knife; onions are done when they're very tender and easily pierced, usually 30–40 minutes depending on heat and onion size.