Place the garlic and salt on a cutting board and mince together. Transfer the mixture to a food processor fitted with the steel blade. Add the egg yolk, lemon juice, saffron, and red pepper flakes. Process until smooth.

With the machine running, pour the olive oil in a thin, steady stream through the feed tube to make a thick mayonnaise emulsion. Transfer the rouille to a serving bowl and store it in the refrigerator until ready to serve.

*RAW EGG WARNING

Food Network Kitchens suggest caution in consuming raw and lightly-cooked eggs due to the slight risk of Salmonella or other food-borne illness. To reduce this risk, we recommend you use only fresh, properly-refrigerated, clean, grade A or AA eggs with intact shells, and avoid contact between the yolks or whites and the shell.