Homemade Dulce de Leche

1 quart whole milk

1 1/2 cups (12 ounces) granulated sugar

1 vanilla bean, split and scraped

1/2 teaspoon baking soda

Combine the whole milk, sugar and vanilla bean in a 4 quart saucepan over medium heat. When the sugar melts and the mixture starts to boil, add the baking soda and lower the heat to low until the mixture is barely simmering. Cook for an hour, stirring occasionally (don't try to incorporate the foam that forms on the top of the milk). Remove the vanilla bean and continue to cook, stirring occasionally, until the mixture is a deep caramel color and has reduced to about 1 cup, about 1 1/2 - 2 hours. Pour through a fine mesh strainer into a measuring cup or clean container, cover and refrigerate for up to one month.