First make sure you are feeding them enough, and make sure it is high quality food that meets their nutrient requirements.

Get them on a regular feeding schedule so they know when and where they will be fed, to prevent food anxiety.

Make a ritual out of their meal times, so it becomes a routine they look forward to and know is their own. As you prepare their meals talk to them, using their names, and the words eat or hungry or meal, words you want them to associate with their meal times only.

Give them each a Spot, where their dishes are placed every time. They will soon learn to wait by their own Spot for their dish.

Cut the quantity you put in the dish in half, and give two servings repeating the rituals, to help reinforce.

This will help them not associate any other time with food, including your meal times.

Never feed them from the table. When giving treats, make a little ritual, where you sit on the floor far away from the kitchen and hand feed them, one at a time, a couple of treats. NO people food.

One thing that confuses me: if they are not allowed in the kitchen, how are they stealing your food? Where do you feed them?