Oli, you know you loves the Spam! Here's my easy recipe - I like when the "teriyaki" sauce that the spam is coated in soaks into the rice a little bit. You get the sweetness from the sauce and the saltiness from the Spam, all balanced out by rice.
1. Ingredients: Spam (I buy the lite kind so I don't feel too guilty that I'm eating meat of undetermined origin), white rice (sure you can probably use brown rice or mixed or rice or even fried rice), soy sauce, mirin, sugar, pepper, roasted seaweed (you can find the half-sheet size or if you get the full-size sheets, just cut in half with scissors - and don't buy the toasted, salted kind).
2. Slice the spam horizontally, about a 1/4 or 1/3 of an inch thick, depending on how Spamlicious you want your musubis. Cook the spam in a pan until both sides are browned. No need to add oil, cuz you know Spam can be oily.
3. In a separate bowl, add about a half cup of soy sauce, quarter cup of mirin, teaspoon of sugar, couple pinches of pepper. You can also add some rice vinegar or pineapple juice to this "teriyaki" sauce. Add this sauce to the hot pan with Spam (about medium heat).
4. The sauce will reduce because of the sugars, but just keep an eye on it so it doesn't burn! After the Spam has been coated on both sides and the sauce has thickened a bit, take it out an put it on a plate. You don't have to use all the sauce.
5. By the time the Spam is ready, the rice should be cooked right? Make sure to use hot/warm rice so that the seaweed will stick. Put a half sheet down with the musubi mold at the bottom.
6. Put a small scoop of rice at the bottom of the mold and spread it evenly. Then place a slice of Spam and then another small scoop rice on top.
6. Press everything into the mold tightly and wrap with the seaweed. If the rice is too sticky or you have trouble unmolding the rice and Spam, wet the mold and press with some water first. Let the musubis cool down a bit, slice in half, and enjoy!