It's Holy Thursday, and Greek restaurants up and down South Halsted Street have less than three days to roast hundreds of young spring lambs, dye thousands of eggs and simmer gallons of special Greek Easter tripe soup.

"It's a really busy day," said Yanna Liakouras, manager of The Parthenon restaurant, which has been serving Greek Easter feasts for nearly four decades. Orthodox Easter falls on April 8 this year, with preparations beginning the Thursday before.

When we visited, the restaurant was calm. A single lamb spun slowly on a spit, fat and juices dripping onto a pan with each rotation. By this weekend, five or six lambs will be turning on the spits at a time, the aroma of roasting herb-scented meat--the smell of Easter for many Greeks--filling the restaurant.

The Greek Easter feast, featuring a lemony tripe soup (called mageritsa) made from innards, spit-roasted lamb and red eggs, marks the end of fasting on Easter Sunday. It's a huge day for Greek restaurants, which serve the meal to thousands of Greeks and non-Greeks alike on both Saturday and Sunday. It's such a busy weekend, diners should prepare by making reservations.

The preparations are many. Part of Holy Thursday is spent dyeing eggs red, Liakouras said. The deep red color represents the blood of Christ, she said, while the egg represents life. Crates and crates of eggs piled high will need to be dyed to have enough to set on restaurant tables this weekend.

"We have these big humongous pots on the stove boiling away with the red dye," she said.

While the eggs are rolling around in the dye on the stove, cooks will begin preparing the mageritsa, a traditional Easter soup often made in the United States with tripe, liver and greens, Liakouras said. In Greece, the soup typically is made with intestines.

Thursday is when cooks wash the greens and clean the tripe, she said. The rest of the soup will be finished Saturday.

As will the roasted young spring lamb, the centerpiece of most Greek Easter meals, she said.

On Saturday, the baby lambs from Colorado -- each 18 to 22 pounds -- are cleaned, washed and filled with salt, pepper and Greek oregano before being impaled on a spit, rubbed with seasoned olive oil and roasted for 2 1/2 hours each, she said.

"Crunchy skin and nice, soft meat," she said. "Baby lambs are fatty. That's what makes them delicious."

By Saturday evening, non-Greeks will be filling the restaurant to enjoy the mageritsa and lamb, she said.

But it's not until after midnight mass that the Greeks arrive, streaming onto the streets of Greektown until the early morning hours of Easter Sunday, many carrying candles from church still lit with the flame passed around during mass.

On that night, most families will have eaten and left by 2:30 a.m. It's not a mob scene, she said.

"We get our fair share," she said. "It's not like the old days. Not that many people eat after midnight mass."

"Sunday is the big day," she said. Families begin showing up around 1 p.m., she said, filling every seat in the nearly 500-capacity restaurant until about 7 p.m.

And all through the day, families will arrive with giant pots in which to carry mageritsa back home. Others will come for cooked spring lambs for their own home feasts. Liakouras said one customer ordered nine young spring lambs for pick up Sunday morning.

The bustle of Easter Sunday brings back memories for Liakouras, who gets a dreamy look in her eyes when asked what her mother served her to break the Easter fast when she was young.

"Fried baby lamb chops and fried eggs," she said. "Doesn't that sound delicious?"