Most haggis you buy (at least in the UK) is already cooked (or at least pre-steamed), so you’re mainly heating it through gently. The key is: don’t let it boil hard or the casing can burst.
Instructions
Wrap the haggis in foil (helps prevent splitting), or prick the casing a couple of times.
Put it in a pan and cover with simmering water.
Simmer very gently (barely bubbling) 45-60 minutes for 1 lb piece of haggis.
Serve by cutting it open and spooning it out.
Done when: it’s piping hot all the way through. If you’re checking with a thermometer, aim for at least 74°C in the centre.
Notes
The larger the piece, the longer simmering or time in the oven:
- 1 lb haggis simmering for ~45–60 minutes and 2 lb haggis ~60–90 minutes.
- Bake for ~60 minutes for 1 lb haggis and ~90 minutes for 2 lb haggis.
No casing haggis in the microwave
Common with vegetarian or pack haggis.
Tip into a microwave-safe bowl, cover, and heat in bursts, stirring once or twice.
Typical is 6–8 min for 1 lb haggis, but follow the pack because brands vary a lot.
Oven method (good if you’re doing a roast-style meal)
Heat oven to 350°F (320°F fan). Wrap the haggis in foil.
Put haggis in an oven dish with a splash of water/stock, cover tightly with foil.
Bake ~60 minutes for 1 lb haggis, ~90 minutes for 2 lb haggis.
Uncover for the last 10 minutes if you want the top a bit drier.
Source
Scottish cuisine, typically served at Burns Night.
Food in Europe