I do not do too much braising but when I do braise and still want the char taste I like to do it under the broiler after I have braise them and removed them from the braising liquid because I find when you char it first and then braise you end up with a great tasting braising liquid but a generally soggy char which is usually undesirable but a lite char first and then a finish after could work nicely for both effects I think I am going to have to try this one now. Whenever I do char in an oven espesially a electric oven I make sure to use a good flavorful sauce of some kind, usually with a decent sugar content because it chars nicely and quickly, but char in the oven doesn't usually give all the flavor as a grilled char so unless you are looking for just the nice light burn taste adding some kind of sauce or rub will give you that more complete tasting char.
Hope that is some help