This is some rich chocolate. The famous Frrrozen Hot Chocolate  at Serendipity 3 will be extra decadent this Valentine’s Day — as it’s being served with an actual diamond. The renowned eatery will be offering an over-the-top version of its iconic dessert with a hollow milk chocolate heart that contains a sparkler ranging from 0.1 to 1.2 carats — valued at anywhere from $15 to $10,000 — for one day only. Customers are served a little wooden mallet with their $29.95 hot chocolate in order to bust