Someone asked the Chazon ish zt'l for advice on how to be less passionate about food. The Chazon Ish zt'l replied, "I am certain that the 'Ketzos' never experienced the taste of kugel." He explained that a person cannot possibly carry two passions with the same intensity in his heart. The Ketzos desired Torah immensely, and automatically, he had less interest in matters of Olam HaZeh. Therefore, when one desires Torah and a connection with Hashem, automatically, he has weakened his craving for food.
Reb Ahron Luria (the Avodas Panim) zt'l asked Rebbe Shlomke of Zvhil zt'l for advice on kedushas achilah, to eat with holiness. Rebbe Shlomke told him, "When you eat, remember that Hashem is present." He said that this counsel is alluded to in Megillas Esther when it states (5:8) אעשה אשר המשתה אל והמן המלך יבוא להם, "let the king and Haman come to the banquet that I will make for them..." This hints that when you eat, invite the King and know that the King is there. You will eat properly when you know that Hashem is present.
Haman, the yetzer hara, will also be at the meal, as indicated by the words המלך יבוא המשתה אל והמן. Haman, the yetzer hara, seeks to entice us to eat in improper ways. But remember that Hashem is present, and with that awareness, you will be inspired to eat appropriately. The pasuk concludes, המלך כדבר אעשה ומחר, "Tomorrow I will do the king's bidding." If you remember Hashem at the meal, then ומחר, "eventually, המלך כדבר אעשה, you will eat as the King desires, properly, as a Yid should.
The Baal HaTanya offers another counsel for kedushas achilah: "When one desires to eat and pushes off the meal for an hour or less, he has conquered the sitra achara below, and Hashem's honor and holiness escalate Above. And because of this kedushah, he will receive immense help from Heaven to succeed in his avodas Hashem."
The Meor Einayim (Matos) clarifies that we can't serve Hashem by eating on levels that are beyond us, but within our levels, we can eat in manners that will elevate the sparks of the food and bring immense pleasure to our Father in heaven.
