I just made a really luscious batch of baconnaise. I thought I'd better write the recipe down in case it turns out well. Usually my baconnaise doesn't actually emulsify properly, and gets all hard in the fridge. But it seems to be pretty good this time so far.
3 egg yolks
2 tbsp vinegar
2 tbsp water
1 tsp sugar
1/2 tsp salt
shake of pepper
1/2 cup liquidy bacon grease*
1/2 - 1 cup high oleic expelled pressed sunflower oil
*Sometimes I get bacon grease that doesn't solidify at room temperature. This is what I used for my baconnaise. If you're using more solid bacon grease, warm it up slowly before using, so it's liquid but not very warm.
Dump first six ingredients into a quart mason jar. Blend together with an immersion blender. Mix together 1/2 cup bacon grease and 1/2 cup of oil in a pourable measuring cup. Slowly add oil mixture into egg mixture while running the blender (you don't have to be very slow. Just don't leave huge puddles of oil on top of the mix).
Once all the oil is blended in, stop and test the mixture. If it's the consistency you like, stop there. If it's thin, continue to add oil slowly until it begins to thicken up, testing frequently to see if you've reached the desired consistency.
If the mix is watery looking and won't thicken up, add another egg yolk.
Good news! It's been a week since I wrote this recipe down, and the baconnaise is still lovely and luscious as ever! I highly recommend it if you've got lots of bacon grease sitting around, or a need for mayo.