I realize 3-days might seem short to some but for the purposes of this thread, let's just say 3 days and if you want to make a 5-day or 7-day kit, you can adjust the quantities.
Let's try to stick to off-the-shelf items and food you can find in grocery stores. I'm more than happy to take a case of MREs and slap a label on it that says "KMAN'S 3-DAY FOOD SUPPLY" but that wouldn't be very creative.

To start it off, here's a recap of what donaldjcheek suggests:
donaldjcheek wrote:3 x candles, 4 to 6 inches in length
1 x small box strike anywhere matches, wrapped in a ziplock plastic bag
1 x large can or 3 x small cans Sterno
6 x envelopes hot chocolate
6 x envelopes instant cider
3 x envelopes instant soup
3 x envelopes instant oatmeal
6 x cans (individual serving size) meat products (Vienna Sausage, luncheon meat, chicken, tuna, etc)
1 x jar cheese whiz or 1 x small box Velveeta cheese
1 x lb bag of instant rice or instant mashed potatoes
2 x stacks crackers (1/2 box)
3 x cans vegetables
3 x cans condensed soup
2 x boxes (at least 12 bars total) breakfast bars or energy bars (take out of the box and place in heavy-duty ziplock bag)
1 x bottle water purifying tablets or a small bottle of household bleach
1 x quart or liter sized cook pot with lid
1 x metal spoon
1 x emergency blanket
1 x small AM/FM radio with extra batteries
1 x small First Aid Kit