Place the macaroni, water, salt and oil in bowl of 7-cup rice cooker. Set rice cooker to COOK. Check macaroni in about 10 minute. If water is almost absorbed, switch cooker to WARM. When water is absorbed, the cooker will automatically switch to keep warm mode, but it's better in this case to catch this before it does. However, if it has already gone to keep warm, it's no tragedy, but some elbows on the bottom may have started to brown (which is perfectly OK). Leave the cooked elbows in the rice cooker's pot.
Add sauce ingredients to cooked macaroni in the rice cooker's pot. Switch cooker to COOK and with lid open, stir until cheeses are melted. Add the ham and peas. Close lid and cook for about 5 minutes, or until sauce is reduced by 25%.
While sauce is reducing, mix breadcrumbs with the melted butter. Set aside.
Preheat oven to 350 degrees. Spray or grease a 1.5 quart deep casserole.
Add macaroni and sauce to prepared baking dish. Top with buttered bread crumbs.
Bake at 350 for 20-30 minutes or until sauce bubbles along the edges and the crumbs are nicely browned.
**For Conventional Cooking**
Cook elbows as per package directions; drain and set aside.
In a medium saucepan ,combine sauce ingredients. Stir constantly over medium heat until cheeses are melted.
Reduce heat and stir constantly until sauce is slightly reduced (about 25%). Add the ham, peas and cooked, drained macaroni. Proceed from here as in the directions above.