MasterChef Australia favourite Chef Lachlan Whittle brings bold Mexican flavours to your barbecue with this standout BBQ prawns recipe. Butterflied U6 prawns are topped with slices of homemade chilli-packed compound butter and grilled over high heat – perfect for Australian summer barbecues and incredibly easy to make on the Big Green Egg.

This barbecued prawns dish delivers smoky, spicy perfection as the compound butter melts and bastes the prawns, creating restaurant-quality results right in your backyard.

Prep Time: 45 minutes (plus freezing time)
Cook Time: 5-10 minutes
Total Time: ~1 hour
Servings: 4-6 as a main
Difficulty: Intermediate

• 400g block unsalted butter (softened)
• 1 dried ancho chilli
• 1 dried pasilla chilli
• 1 dried guajillo chilli
• 1 dried morita chilli
• 1 de arbol chilli
• 1 tbsp achiote paste
• 2 garlic chives
• 1 tbsp salt
• 3 cloves garlic
• 1 chipotle chilli in adobo (from can)
• Rind of 1 lime
• Juice of 1 lime
• 1 tsp ground cumin

• Size U6 prawns (butterflied through the back and cleaned)
• Lochy Cooks ‘Cinco Chili Rub’ (for seasoning)
• Lochy Cooks ‘Smoked Pineapple Habanero Hot Sauce’ (for serving)
• Fresh coriander and lime wedges for garnish

1. De-stem and de-seed all dried chillies and cut with scissors into chunks.
2. Toast chillies in a hot dry skillet or pan for 30-45 seconds (be careful not to burn as it will create bitterness).
3. Once toasted, let chillies cool and grind in a spice grinder until small but still chunky.
4. Toast the achiote paste briefly in the pan to fry it out, then add to the spice grinder and blend with the chillies.
5. Add the blended chilli and achiote mixture to a mixing bowl with the softened butter.
6. Add finely chopped garlic and finely chopped garlic chives and mix well.
7. Add all remaining ingredients (salt, chipotle in adobo, lime rind, lime juice, cumin) and mix until fully combined.
8. Cut a square of baking paper, add half the mixture in a line across the paper, roll into a log shape, then wrap tightly in cling film. Repeat with the remaining mixture. Place in the freezer (will last 6-12 months).
9. Set up your Big Green Egg for direct high-heat grilling (around 250-300°C).
10. Open up the butterflied prawns and press against a surface to keep them flat.
11. Flip prawns over, lightly oil and season generously (ideally with Lochy Cooks ‘Cinco Chili Rub’).
12. Slice the frozen compound butter into 5mm discs.
13. Place butter discs on the body and head of each prawn.
14. Grill over high heat on the Big Green Egg for 3-4 minutes until the prawns are just cooked and the butter is melted and bubbling.
15. Rest briefly, then squeeze over fresh lime juice and scatter with finely chopped coriander. Serve immediately with Lochy Cooks ‘Smoked Pineapple Habanero Hot Sauce’ for extra authentic Mexican flavour.

Big Green Egg Tip:

Get the grill screaming hot with the cast iron grate for incredible sear marks and that signature Big Green Egg charcoal flavour. The ceramic retains heat perfectly for consistent high-temperature cooking.

Recipe created exclusively for Big Green Egg Australia by Chef Lachlan Whittle.

Tag us @biggreeneggau and @lochycooks when you make these prawns – we can't wait to see your cooks!