Sisters Katherine Kallinis and Sophie LaMontagne learned to bake from their Greek grandmothers—growing up, the older women would let the girls pour leftover cake batter into two tiny cake pans. They loved to watch their miniature cakes rise next to the bigger one in the oven. “We got a big kick out of that,” says Sophie, 31.

The fond memories of those rudimentary cupcakes prompted the Toronto natives to quit their jobs in May 2007—Katherine, 29, was an event planner for Gucci, and Sophie worked in private equity—to open Georgetown Cupcake (1209 Potomac St., NW; 202-333-8448) last February. Now customers line up outside the teeny shop daily to try the petite sweets, whose 20 rotating flavors include chocolate-mint, lava fudge, and most popularly, red velvet.

Judging by the bakery’s loyal following, it’s clear the sisters have come a long way since their early days in the kitchen: “Sometimes our grandmother would ask us to sift the flour,” recalls Sophie, “but it was really hard and tedious, so we would just dump the flour in when she wasn’t looking. Now we’ve learned that you can’t cut corners like that.” The sisters recently took a break from the oven to let us in on their foodie favorites.

Fridge staples:
Sophie: Sparkling water and Diet Coke.
Katherine: Greek yogurt, honey, and vitamin water.

Favorite thing to cook besides cupcakes:
Sophie: Frittatas. I like to be creative with whatever we have in the fridge—fresh herbs, goat cheese, different kinds of ham, bleu cheese, smoked salmon.
Katherine: Meatballs. I used to make them with my mom. We experiment a lot, but the basic recipe includes a lot of Parmesan cheese, bread crumbs, fresh parsley, and tons of garlic—I’m a big garlic person.

Preferred guilty-pleasure food:
Sophie: All French fries.
Katherine: Lay’s barbecue potato chips.

Favorite grocery-store candy bar:
Sophie: Twix.
Katherine: Kit Kat.

Coffee drink of choice:
Sophie: Vanilla soy latte from Buck’s County Coffee.
Katherine: Pumpkin-spice latte with whipped cream from Buck’s County Coffee—yum!

Favorite restaurant:
Sophie: Cafe Milano. I like all the pasta dishes there, and it’s pretty convenient to our shop. It has a fun atmosphere and good prices for wine.
Katherine: Ray’s the Steaks. Oh, my gosh, I love the filet mignon!

Favorite pastry chef in town (besides your sister!):
Sophie: We don’t know a lot of the chefs, but we both love the chocolate-strawberry bombe at Cafe Milano.

Cocktail of choice:
Sophie: Any and all Champagne.
Katherine: Kir royale.

What was the worst fight you ever got into with your sister?
Katherine: When Sophie was eight and I was six, she threw my Barbie off our balcony and broke her leg. We didn’t speak for weeks.