The normal AFM information for a turning escape procedure uses 15 degrees bank angle.
There is nothing sacrosanct about that angle.
Sometimes we schedule a lesser bank for the escape to achieve a larger turn radius, say, to suit some terrain on the inside of the turn. In that case we either stick with the climb degradation associated with the turn as scheduled in the AFM or redo the sums to get a lesser penalty.
Sometimes we need a tighter turn which requires a higher bank angle and a similar process can be applied. However, there are practical limits to this as the climb penalty goes up fairly rapidly.
Depending on jurisdiction, one may need to involve the Regulator in such antics.