Sometimes, a mishap can lead to a delicious result. When I started creating this treat, I was definitely craving pumpkin but I had also planned on mixing in peanut butter. The only problem: I could not — with all of my might — open the darn jar! Seriously, could not open it. Ugh. Luckily, I had a jar of pumpkin butter (that I could actually open) in the pantry that would have to do as a substitute. With a late summer in…