Place the sauteed red onion, coriander, salt, pepper and pumpkin into a large mixing bowl or food processor (if you have one). If mixing by hand you will need to dice the roasted red onion before popping into the bowl. You may need to mash the pumpkin a little with a fork a little then Mix all ingredients with a wooden spoon until well combined.
If using a food processor just add all the above ingredients and pulse until combined (about 1 -2 minutes).