Caravan 208B Captain reported a loss of bank control while flying an approach in instrument conditions; resulting in an unstablized approach. The Captain regained control of the aircraft and performed a go around then returned for another approach.

Narrative

It was an LIFR day. Approach gave me 'best forward speed' for the approach to XXC. I don't remember if they said to the numbers but I do remember something to the effect of 'as long as possible'. I tried to rapidly configure the aircraft for landing by about 1000-1100MSL. I had a lot of speed and ballooned quite a bit when I dropped to flaps 20. I started to lose the glide slope and dove to recapture. My needles started dancing and I realized I was totally unstable. By this point; I had gotten way behind the aircraft and found that I had rolled to the left so much that I was in an unusual attitude. I rolled level; applied takeoff power (almost firewalled it) and pulled the nose up hard while keeping my eye on the airspeed to avoid stall. Once I had the airspeed and a positive climb; I called missed. I remember being at about 900MSL when I noticed my roll and began to recover. I know I did not go below DA because on my second attempt; I broke out maybe 10 feet above minimums and was able to see the runway. My first attempt I was IMC the entire time.This flight showed me a limit to my skill level in this aircraft with the avionics on board. Previously; best forward speed instructions were close to but not AT minimums. In the future; I will communicate with ATC for resequence or another runway so that I am able to maintain a stabilized approach with the correct configuration.