I did some experimenting the other night and ended up adding 2 scoops of protein powder (I used Any Whey unflavored protein instead of Syntrax). In addition, I used half the butter and almonds. I also swapped (and slightly increased the amount of) skim milk for the heavy cream.
I got it down to 208 calories per 6 bars (18g protein, 13g fat, 4 net carbs).
If I cut it into 8 bars, the calorie count goes down to 156 (14g protein, 10g fat, and 3 net carbs)!
The bars are sooo yummy! My husband was BEGGING me to let him lick the bowl!