In a high speed blender or food processor, add bell pepper and process until finely chopped, pausing and scraping the walls once. For a thicker consistency sauce, drain the juices.
Add mustard, honey and pepper flakes. Then process on Low just enough to combine. Add more red pepper flakes for more heat kick, if you wish.
Notes
Store: Refrigerate in an airtight container for up to 7-10 days.Freeze: In small portions, in airtight container, for up to 3 months. Thaw and give it a stir as water might accumulate on top.