Prepare a baking sheet by lining it with a silicone liner, or foil sprayed with nonstick cooking spray. Rub the lemon juice into the sugar until it is well-distributed and the sugar is slightly damp from the juice. This will help prevent crystallization when you caramelize the sugar.

Place a small pan over medium heat and let it preheat for several minutes until the pan is hot. Add the sugar, and begin to stir immediately and continuously. Continue to cook the sugar, stirring constantly, until it liquefies. Shortly after it becomes liquid it will start to color. Cook the caramel until it is a medium amber color. It will have a strong smell of caramelized sugar at this point. Be careful not to cook it too long, or it will blacken and become burned.

At this point, you have some choices. You can pour the hot sugar out onto the prepared tray into a thin, even layer, let it harden, and then smash it into shards to put on your hot chocolate. You can let it cool slightly, then drizzle it in circles or other random patterns, let it harden, then break the patterns into pieces. Or you can try to make shapes: let the sugar cool slightly, so that it's a little bit thick, and use a spoon to dollop it onto the baking sheet in circles, ovals, or even heart shapes. Most of all, have fun! If at any time it gets too thick to work with, return the pan to the heat briefly and stir while it warms up.

Let the caramelized sugar cool completely before touching or moving it.

Choices: can drizzle on Silpat or sprayed foil to get shapes, can let it cool a bit and drop it into circles or shapes from a spoon, or can pour it out onto a pan, let it harden, then shatter it with a knife/meat mallet.

Combine the milk, cream, brown sugar, vanilla bean paste, and salt in a medium saucepan. Place the pan over medium heat, and bring it to a simmer, stirring occasionally, until bubbles start appearing along the sides of the pan and it almost comes to a boil.

Remove the pan from the heat, add the chopped white chocolate, and whisk it until the chocolate melts and the mixture is smooth. Divide it between 4-6 cups, topped with additional whipped cream, if desired, and finish with your crunchy caramel decorations or sprinkles. Enjoy immediately.