Lidia Kieca bought her paczki on Feb. 20, when Paczki Day is celebrated in Poland.

Kieca also bought some Monday to send overnight to her adult daughter in Nashville, Tennessee, where she said the traditional Polish pastries are harder to find.

And she was back at the bakery on Tuesday, when Paczki Day is celebrated in Chicago and other U.S. cities with large Polish populations, carrying pastry-filled boxes stacked up to her chin.

For Kieca, whose parents are Polish, the bready dough — fried and stuffed with a myriad of jams and custards — are fun. They’re “part of growing up, part of our tradition,” she said.

They’re also a reminder “you’re not supposed to eat this type of stuff after today,” she said, laughing.

For many Poles, both in the U.S. and beyond, Paczki Day is the kickoff to Lent, the 40 days of fasting and prayer that Catholics and many other Christians in liturgical traditions observe leading up to Easter.

But one needn’t be religious to enjoy a paczek.

“Some people have waning beliefs on their religion, but even if you’re not, you know, 100% Catholic, you’re still 100% Polish Roman Catholic because everything in Polish tradition and the holidays is revolving around the church,” said Bartlomiej Kolatek, general manager of Kolatek’s Bakery on the Northwest Side of Chicago.

In the U.S., Paczki Day comes on what others may call Fat Tuesday or Shrove Tuesday, a day some celebrate by eating pancakes.

The idea is the same: To feast before Lent begins on Ash Wednesday — and maybe to use up some of those tempting foods in the cupboards, like sugar and butter and alcohol.

No less than six of the paczki available this week at Kolatek’s Bakery include fillings flavored with alcohol, including rum and an egg liqueur called advocaat.

“Basically, paczki are made to get rid of all your stores of fatty and decadent foods, and that’s a great way of doing it in one fell swoop,” Kolatek said.

“So if you’ve got that bottle of vodka that you want to get rid of, you know, put some in the flavor in the filling.”

Kolatek was born in Poland and grew up in the bakery his parents started 35 years ago, originally on Chicago’s South Side. In recent years, the family-owned business has focused on freshly baked, health-conscious breads — when it’s not frying the more than 25,000 paczki it expects to sell this week, he said.

The bakery sells 24 flavors of paczki during Paczki Week, between the Polish and U.S. observances of Paczki Day, he said.

Those fillings include traditional prune, or “plum butter” as the bakery more appetizingly calls it. It’s still the bakery’s most popular because of the “childhood nostalgia” — it’s the paczek everybody remembers eating as kids, he said.

The bakery also popularized rose-filled paczki in Chicago after it started importing jam made from rose petals picked by “a few older ladies in our village back in Poland,” he said.

The bakery sells “premium flavors” like caramel bacon, strawberry cheesecake and Nutella, too.

And it’s not just the fillings that have gotten a modern spin, plain custard giving way to chocolate chili.

Paczki Day now is celebrated with paczki selfies, paczki memes, even “paczki wars” in workplaces across the city as employees bring boxes of pastries with outlandish fillings to share, according to Kolatek. No grocery store jelly doughnut parading as a paczek is going to end up on Instagram, he said.

“This is very huge on social media, and that’s cool ’cause it’s like old tradition with new technology,” he said.

But the point of Lent isn’t necessarily taking selfies or giving up sweets, according to the Rev. Marek Smolka, associate pastor and director of liturgy at Holy Name Cathedral in Chicago.

“We should just focus on our relationship with the Lord and with other people as well,” Smolka said.

Still, the priest doesn’t see the tradition as a distraction from Lent. Rather, he said, for some people the filled pastries are a “wake-up call.” When paczki appear on bakery shelves, they know it’s time to prepare for the penitential season.