I've tried a couple of different recipes for mayonnaise recently. What I've learned is not to use a heavy extra virgin olive oil. My original attempt was very bitter. 

For this recipe, I used an "extra light tasting" olive oil. It did the trick! You can experiment with flavors by substituting your fat and adding other ingredients. Try it with bacon fat or coconut oil. Add some fresh herbs or a little chipotle pepper. Enjoy it free of guilt! Your mayonnaise will be a beautiful buttery yellow and should stay good for up to a week if refrigerated in an airtight container.

Adapted from Paleo Diet Lifestyle.

Ingredients
2 egg yolks
1 tsp mustard
3 tsp lemon juice
1 cup extra light olive oil
sea salt
freshly ground black pepper

Procedure

1. In the bowl of a food processor, add egg yolks, mustard, and 1 tsp of lemon juice. Process until smooth.
2. With processor running, VERY slowly add olive oil through the feed chute until you form an emulsion. If you pour the oil too quickly, it will separate and you will probably have to start over.
3. Continue to add the oil until the mixture thickens. 
4. Add the remaining lemon juice and pulse to combine.
5. Add salt and pepper to taste.

Source:
http://www.paleotable.com/2011/01/paleo-mayonnaise.html 

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