Discomfort in throat causing sneezing especially after eating chocolate, bitter taste in mouth, and frequent need to clear throat /acid reflux or not?

Acid reflux. If you are having acid reflux your doctor can order tests to see how often. A ph probe is placed and studied for24 hours. You can try over the counter medication. Ask your pharmacist. Try to stop caffeine and write down what makes it worse.
Chocolate. It sounds more like you have a choclate allergy.See an allergist to get tested.
Reflux more likely. You appear to have both acid and bile reflux which can really irritate and inflame your throat see GI doc.