Place a large pot with a thick bottom and high walls, on your cooktop and turn to low-heat.

Mix the milk, heavy cream, vanilla, baking soda, and sugar into the pot. Stir with a whisk until all the sugar dissolves.

Cook over low heat, uncovered, for about an hour. No need to stir now. You will only notice that the milk takes on a subtle light-yellow color.

Continue cooking for one more hour. You will notice that the mixture begins to take on a light-beige color. No need to stir.

After the first two and a half hours have passed. You should start stirring, without stopping for approximately 20 minutes.

You will know your dulce de leche is ready when you try to spread it on a cold plate.

Once the dulce de leche has the desired consistency and beautiful golden-brown color, turn off the heat and allow it to cool.

Once the dulce de leche is completely cool, transfer the caramel into a clean, dry glass jar and enjoy.