Combine egg, 1 teaspoon olive oil, and the salt in a blender, and blend at lowest speed.
With blender still running, add remaining olive oil and the safflower oil in a slow, steady stream, and blend until incorporated (if you prefer a thicker mayonnaise, blend 10 seconds more at a higher speed).
Transfer mayonnaise to a bowl, and stir in lemon juice. Serve immediately or refrigerate up to 2 days.
Note: The egg in this recipe is not cooked.