Ingredients

• 1 large egg yolk
• 1 teaspoon Dijon mustard
• 2 tablespoons fresh lemon juice
• 1/2 cup grapeseed oil
• 3/4 cup olive oil
• 6 anchovy fillets packed in oil, drained, very finely chopped
• Kosher salt, freshly ground pepper

Instructions

1. Whisk egg yolk, mustard, and 1 teaspoon lemon juice in a small bowl. Whisking constantly, gradually drizzle in grapeseed oil, then olive oil, drop by drop at first, until mayonnaise is thickened and smooth. Whisk in anchovies and remaining lemon juice; season with salt and pepper. Cover and chill.
2. Do ahead: Mayonnaise can be made 1 day ahead. Keep chilled.