"Can you somehow get a maillard reaction to occur in a rice cooker? Or caramelization?"
You can use ingredients that already have these. Like I use onions I caramelized before hand and top a lot of my dishes with meat that I browned. You can get some browning in a rice cooker if you need to though. Actually some rice cookers are made specially to do that. The ones that target the Middle Eastern market produce rice with something called a "tadig" which means that the bottom rice has turned crispy and brown- ideally with ghee put in the bottom of the pot before the rice was added. My rice cooker produces that and I typically take it out, break it up, and mix it in with the dish so there are lovely crunchy bits.
You can use ingredients that already have these. Like I use onions I caramelized before hand and top a lot of my dishes with meat that I browned. You can get some browning in a rice cooker if you need to though. Actually some rice cookers are made specially to do that. The ones that target the Middle Eastern market produce rice with something called a "tadig" which means that the bottom rice has turned crispy and brown- ideally with ghee put in the bottom of the pot before the rice was added. My rice cooker produces that and I typically take it out, break it up, and mix it in with the dish so there are lovely crunchy bits.