Russian Walnut Shaped Cookies - "Oreshki" - Olga's Flavor Factory

Ingredients

• 2 large eggs, room temperature
• 1 1/2 cups granulated sugar
• 1 cup butter, melted and slightly cooled (16 Tablespoons)
• 3 1/2 Tablespoons mayonnaise
• 1/2 cup sour cream
• 1 teaspoon baking soda dissolved in 1 teaspoon vinegar
• 4 - 4 1/4 cups all purpose flour (start with 4 and only add more if you need to)
• 1 1/2 (14 oz) cans dulce de leche (cooked condensed milk (21 oz total))
• 1 cup butter (or 16 Tablespoons, room temperature)
• 4 oz cream cheese (room temperature), optional
• 1 teaspoon vanilla extract