Preheat the oven to 350 degrees F (175 degrees C).
Place sweetened condensed milk, evaporated milk, eggs, cream cheese, milk, and vanilla extract in a blender; blend until smooth.
Place sugar in an even layer in a saucepan over medium heat. Cook until the edges start to brown, about 1 minute; drag sugar into the center with a spatula once the edges start to brown. Continue cooking, stirring from time to time, until caramel is an even golden brown, 4 to 5 minutes.
Meanwhile, pour 1 inch boiling water into a large oven-safe pot or baking dish to make a water bath.
Pour caramel into a 9-inch flan mold or baking pan; swirl so that caramel reaches 1 inch up the sides. Pour the condensed milk mixture on top. Set in the water bath.
Set the flan and water bath in the preheated oven; bake until a damp table knife inserted into the center comes out clean, 45 minutes to 1 hour. Remove from the oven and let stand for 5 minutes.
Chill flan in the refrigerator until firm, 2 to 3 hours. Invert onto a serving plate so that caramel is on top.