MapMyRide, I burned over 2000 calories during my 60-mile ride and nearly 2500 calories during my 70-mile ride (a loop to Los Lunas and back). That sounded so incredible, that I did a quick estimate of how many calories I consumed while riding... On the 60-miler: some fruit & nut trail mix, gatorade and peanut-butter cookies. It's possible that that added up to 900 calories. But on the 70-miler I only had the trail mix, so more like 400 calories. Apparently most of the calories for these rides get eaten in the days before and after the ride.
The photo is my new perfect bike food: trail mix with pretzels mixed in for extra carbs and salt. I tried eating runner's goo when I trained for a marathon, but it gave me a stomach cramp which defeats the whole purpose of the terrible tasting stuff. So I stick to real food.