You CAN teach a dog not to bark incessantly!!!
The secret is to turn barking into a "learned behavior" like sitting or heeling. You are unlikely to eliminate barking altogether, but you can minimize it. You kind of walk a fine line between wanting the dog to be protective, just not obnoxious.
It takes a while (weeks? depends on dog) My mom and I have used this technique on several of our dogs. Works well if you are patient and consistent. (Personally, I think no-bark collars are awful!) This may not work for you if you have to place Pepper in a new home, but her new people may be interested.
Step 1 - teach the dog to bark on command - Say"speak" when the dog barks and reward. Repeat until he/she will bark when you say speak.
Step 2 - connect barking at stimulus (doorbell) to the speak trick. When dog barks at doorbell, say "good speak!" and reward dog - sounds counterproductive, but bear with me.
Step 3 - Control the behavior. When the bell rings, dog barks, you say "good speak" and act as if it's a training session and go on to another command, like sit or down. This should distract the dog from barking. (Then answer the door) Eventually the dog "gets" that you are acknowledging the alert bark and will just bark a couple of times then stop.

Another version of this is to train the dog to respond the the stimulus (doorbell) with another behavior. A friend of mine trained her dog to go to his bed and sit down. Door rings, he barks once, runs to bed and waits for her to release him from the "trick."

FYI - If Pepper is hearing impaired, make sure you couple all verbal commands with gesture commands.

Good luck.