If you have an immersion blender, it takes literally 2 minutes, and is fool-proof. Doing it other ways, such as manually or a food processor is a little trickier. I've done this way now for a while and never need to buy mayonnaise anymore. Kenji has a vegan recipe too using aquafaba if you're in to that.
https://www.seriouseats.com/recipes/2011/10/two-minute-mayon...
If you have an immersion blender, it takes literally 2 minutes, and is fool-proof. Doing it other ways, such as manually or a food processor is a little trickier. I've done this way now for a while and never need to buy mayonnaise anymore. Kenji has a vegan recipe too using aquafaba if you're in to that.