In a heavy saucepan, sauté the onions with the 2 tbsp. olive oil over medium/ high heat. Stir occasionally until golden brown and caramelized. Remove from heat and cool down.
Pulse the garlic cloves in a food process fitted with the regular blade. Once gloves are chopped to tiny pieces, scrape off them off and move to the center of the processor bowl.
Add the almonds, hazelnuts, pepper flakes and bread to the bowl and process until a paste is formed. This part needs patience as it could take a few minutes until it thickens into a paste.
Scrape off the sides of the bowl and add in the caramelized onions, red peppers, tomatoes, parsley, paprika, salt and pepper. Continue processing until the mixture is smooth and while it is running, add the vinegar and then slowly drizzle in the 1/4 of olive oil and thinning it out as much as you desire. You don't need to use all the oil if you feel the sauce's thickness is to your liking.
Let it sit at room temperature for at least an hour for all the flavours to blend better.
Spread it over chicken, fish, a crostini, or be adventurous like my kids and mix it with your rice and stew. Hope you enjoy, buen provecho!