Your viewer should drool over your photograph. That's your goal.
Setup - Talk to your food stylist or marketing manager first about what they want to show. They're most likely looking for what the client wants. That's usually appetite appeal, which translates to texture, glistening sauces, distinctive colors. Then feature the client's product with all of those things.
Recipe - Choose camera angle, then make lighting choices to enhance the food product. I use the main light for texture, lighting from a low angle - graze the food with the light. You want shallow shadows, usually backlit or crosslit from the sides. That minimizes undesirable shadows on the food and separates it from the background. It can also give you rim-lit highlights or translucence in the food or drink.
Use other lights to fill shadows or a mirror for very focused fill. I usually use the narrowest-possible strobe angles to focus light, with snoots or grid-spots for even more focus.
I'll re-heat or place fresh, heated food in just before shooting for the best look.
Ingredients - I most use a Canon EOS 5D mark II and EF70-200mm f/2.8L IS lens, depending on the subject, always tripod-mounted. I also carry an old EOS 1D mark II as a backup camera. An EF24-70 f/2.8L may work better in some situations. I'll use a short extension ring with any lens if I need to get closer.
I use an ST-E2 to control three or four Canon strobes on light stands (two 550EX, two 430EX, all in manual power mode), with anything from plain white/gray to faux-wood or place mat backgrounds. 6-foot wide gray or black roll-paper works well as a substrate for the food set, wound up and behind the set. I also use ceramic plates shaped and colored to complement the food. I prefer minimalist composition, without too much in the picture.
Added spice - Backgrounds are important - get rid of anything that distracts from the food. Talk to the stylist or marketing manager about what should be sharp, then isolate with depth of field to suit. A 45mm or 90mm TS lens might come in handy, but I've never used one to do this. My 24mm TS-E puts me too close.
You’ll want longer focal lengths for longer working distance, even in a very small food studio.
Auto white balance in Canon's most recent dSLRs works pretty well (DIGIC 4). Avoid mixed light sources - it should be all strobes or all incandescents or all natural light, not some combination. Use a color-calibrated monitor to judge color afterwards. You can color-correct in Lightroom or Photoshop, but always try to get it right in the camera.