Place the canola oil, olive oil, egg, lemon juice, white vinegar, and salt in a tall glass jar.
Using a handheld immersion blender, process everything together to a thick mayonnaise-like consistency, about 10 to 15 seconds.
Spoon the homemade mayo into a bowl. Add the basil pesto and stir gently to combine.
Store the pesto mayo in a clean glass jar with an airtight lid in the fridge for up to one week. Use anywhere you would use mayonnaise.
Notes
A jar just wide enough to fit the head of your immersion blender helps the mayo emulsify quickly and evenly.
Make sure the immersion blender is resting at the bottom of the jar before you start blending.
Blend without moving the blender until the mixture starts to thicken, then slowly lift to incorporate the rest.
Stir the pesto in gently so you don’t break the emulsion.
Storage
Store homemade pesto mayo in a sealed jar or an airtight container in the fridge. It will keep well for up to one week. Stir gently before each use if any separation occurs.