1. Combine peppers and shallot in a food processor. Process until finely chopped. Transfer to a glass jar, cover, and let sit at room temperature overnight.
2. Add orange zest, juice, and vinegar and stir to combine. Cover and let mixture sit in the refrigerator for 1 day. Transfer to blender and blend until smooth. Strain mixture through a fine-mesh sieve and into a clean glass bottle or jar. Seal tightly and store in refrigerator.