Picking up a lot of observations/complaints about coffee and food in
Flaine. I ski there regularly and have a place in Samoens. Our favourite place to lunch is Le Blanchot, halfway up the valley in Flaine. Prices for the area are (or at least were last year and in the past) pretty reasonable. Always, the best deal is the Plat du Jour. Different every day. If that sounds too heavy, try the Salade du Montagne. Excellent. Two other places offer great home made dishes as well. The little restaurant at the bottom of the Les Molliets Chair. It has the best blueberry tart in the world. Finally, the restaurant, La Luge a Teran over on the Samoens side is special. At the bottom of the Damoiseaux chair (often not running but you can easily ski in and out). Reservations are necessary but you can call them and book ahead. Again, plat du jour is the way to go.
I've always found the coffee to be consistent with French restaurant coffee. That is to say pretty strong. In general, avoid the cafeteria type restaurants and try to go with the plat du jour. It is all home made on the mountains and is fresh.
I agree with the caution about Cascades. Great to do. Once. Do it early in the day so as to avoid the traffic jam that can occur on the switchback. do not do this if you are not comfortable with narrow pistes.