Every time I try to caramelize onions on the stove they go from "barely browning" to "scorched edges" in about 90 seconds. I've tried lower heat, more butter, a heavy-bottom pan, stirring constantly, not stirring at all. Best I've managed is uneven brown patches with crispy bits I have to pick out. What am I missing — is it the heat, the pan, the cut, or just patience?
