To make homemade dressing, add ingredients to a tall glass. Using an immersion blender, blend on high. While blending, slowly pour the oil in, moving the blender up and down to help the mixture come together. Continue adding oil and blending until a thick and creamy spread forms. This takes about 1-2 minutes. Store leftovers in an airtight container in the refrigerator for up to 2 weeks.

To assemble tuna salad, stir all ingredients together in a mixing bowl. Season with salt and pepper. Serve on crackers, over bread, or with fruit and vegetables.