In a pot of boiling water, cook the macaroni until just near tender, do not over cook, basically under cook it by a minute or so. Drain and rinse under cold water, the cold water will stop the cooking process.
Add all the ingredients to your slow cooker and give it a mix. Cook on Low setting for 3 hours or High setting for 2 hours, stir once or twice during the cooking but quickly so not all the heat is let out of the cooker. Serve.
The cheese is the costly part here, 180 Baht/250 gram block. For 6 servings, this is about 88 cents per serving.