Making dulce de leche using sous vide is about as mindlessly simple a process as you can hope. You can cook the sweetened condensed milk in the can if you’d like—many do—but I pour the can into a jar I have sized just for this (and that same jar then stores it in the refrigerator).
Other folks cook theirs for 12 hours but I push mine to 15 hours for a more golden flavor. Set the cooker to 185f and drop in your can or jar.
This got me to thinking: “Can I make browned butter the same way?”
Today I am trying a cube of butter as 185f for 12 hours and we’ll see what that does. On-line I saw many folks claiming you can’t do it because the water will prevent the browning. I am rightly dubious about this claim. Sweetened condensed milk is about 27% water while butter is only about 16-18% water. If I can caramelize the sugars in sweetened condensed milk with nearly twice the water, I ought to be able to do similar in butter.
We shall see.