Cut the onion in half and cut into thin slices. In a sauté pan over medium heat, warm the oil. Add the onion slices and cook until they are soft and a caramel color, approximately 40 minutes. You will need to stir often to prevent burning. Reduce the heat to medium-low if the onions are turning a darker color too quickly.

Once the onions are the color of maple syrup, add the brandy and deglaze the pan until the alcohol burns off. You will know when there is no longer a smell of liquor and the onions are only slightly moist.

Measure out 2/3 cup of the onions. If there are extra, use them to flavor soups or to spread on toast. Place the 2/3 cup in a saucepot over high heat with the cream, milk, sugar, vanilla, and salt. Bring just to a boil and remove the pot from the heat. Do not allow the cream to boil over. Set aside to steep and cool for 15 minutes.

Transfer the dairy and onion mixture to a blender. Blend until smooth and creamy.

Place the ice cream base in a shallow metal pan. Stir in the chives and peanuts, if desired. Place the pan in the freezer. Stir every 20 minutes for approximately 2 to 3 hours until the desired consistency is achieved.

Scoop or spoon into bowls and enjoy.