I'm so sorry that Boris has been so poorly.
Our Biggles had two similar attacks - in quick succession - at the end of 2013. He recovered after hospitalisation for the first attack but was undiagnosed, hence the second a couple of weeks later.
It was awful and he suffered terribly, so subsequently we've taken no chances whatsoever with his diet. He has no treats or titbits ever, just a great quality, low fat diet.
Research that we did at the time (and advice that lovely friends gave us) suggested that dry food below 10% fat was generally well tolerated by dogs with pancreatitis, so being super-cautious and very risk averse I've tried to keep Biggles below 5% to allow margin for natural variation and mishaps (like when he shoves his head in others' bowls!).
None of this is particularly scientifically researched, but what has worked fabulously for Biggles for the past 14 months is as follows:
Three meals a day: Two kibble based, one pasta based.
Kibble: Wainwrights grain free, white fish and vegetables variety (naturally low fat).
Pasta: Any wholemeal pasta (or normal, but wholemeal is better for fibre).
Added to the above we use any of the following:
Tinned food: Butchers Lean and Tasty (comes in two varieties - gravy or jelly - both are low fat and he loves them) or Chappie Original (NOT the other flavours, just Original is fish based and low fat).
Tasty toppings: Sweet potato; tuna steak in spring water; non-fat cottage cheese; lean meat (chicken breast, turkey breast, pork tenderloin) slow-cooked in water to further reduce fat (throw the fatty water away); blended vegetables (peas, carrots, squash, cauliflower, sprouts).
I know the above probably seems ludicrously over-cautious, but Biggles is an elderly gent now (he's nearly 14) and has some other health issues, so he genuinely wouldn't survive being so poorly again as he was with pancreatitis. Friends have had success reintroducing other foods gradually, but that's a chance we felt we couldn't take with Biggles.
I'm happy that two Wainwrights meals a day are nutritionally complete anyway, so the toppings are just to keep things interesting for him. His additional pasta meal provides a calorie boost so has ensured that he's able to maintain his weight despite his food generally being quite low-calorie through being low in fat.
I'm not sure whether the above would suit a young and active dog, but for our old boy it's worked a treat and kept him well.
Good luck
Jo
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As I understand it any food should be ok as long as it's below 3% fat. You might find a basic mixer meal would be ok and add home cooked to it rather than cooking the lot. 
