Epicurious.com did not have a recipe for haggis, but Foodnetwork.com did. Here is the list of ingredients:
1 sheep stomach
1 sheep liver
1 sheep heart
1 sheep tongue
1/2 pound suet, minced
3 medium onions, minced
1/2 pound dry oats, toasted
1 teaspoon kosher salt
1/2 teaspoon ground black pepper
1 teaspoon dried ground herbs
In case you're so inclined, you can find the rest of the recipe here. The recipe ends with the advice, "Serve with mashed potatoes, if you serve it at all."
Okay, then! Let's not do it and say we did. How about, instead, the first two stanzas of his poem, "Address to a Haggis" (in English translation):
You'll find more about haggis and the rest of the poem here. You've got to admit, Burns had a sense of humor. Well, all the Scots, if you think about their apparent adoration of that recipe.
A blessing on your honest, hearty face,
Great chieftain of the sausage race!
Above them all you take your place,
Stomach, tripe, or chitlins,
Well are you worthy of a grace
As long as my arm.
The groaning trencher there you fill,
Your buttocks like a distant hill,
Your skewer would help to mend a mill
If time of need,
While through your pores the flavors distill
Like amber bead.