Hilary Duff is all grown-up—and looking better than ever. The 27-year-old erstwhile Lizzie McGuire star covers the latest issue of Shape magazine, looking absolutely gorgeous as she flaunts her super-toned tummy and killer abs. So, what's her secret to success as a busy mom of three-year-old Luca? It's all comes down to cutting herself some slack. "There's so much pressure to always have it together, and I'm not falling for it," she tells the mag. "You see supermodels who have babies, and the next week they look as if they were never pregnant. That was not the case with me. Some days I feel great, others I feel pretty normal, and that's acceptable." While Duff isn't afraid to get candid about her diet philosophy, she admits she's not a fan of restricting what she eats. "I rely on grown-woman food. I'd rather have someone pull my fingernails off than hunker down and go on an actual diet," she says. "It's so hard for me! My sister Haylie and I once considered doing a baby-food diet, but it just sounded too disgusting." As for her exercise regime? "I don't do auto-gym. I go three times a week and mix it up every time," she shares. "I work out with weighted balls, battle ropes, and big rubber bands. I do this thing with a sledge-hammer where I swing it and hit a rubber block, and it get out all of my aggressions. Everyone is like, ‘Uh-oh, Hilary's got the hammer—get out of the way!' "I rely on real-life exercise," the blond beauty continues, "Carrying my son, for one. He weighs 35 pounds. The other day we went to Disneyland and he fell asleep in my arms, and I had to carry him back to my car, which was a 30-minute walk. I was dying." Although Hilary works hard to stay in shape, the hot mama also confesses she couldn't live without her guilty pleasures. "The key to a happy life is cheese. It's a real problem. I can't say no to it!" she reveals. "There's a cheese shop in Beverly Hills, and my car is like a magnet to it. Luca is crazy about it, too. Love the cheese!" (We feel you, Hil). Still, when the hot mama does feel the need to shed a few lbs., she turns to her favorite foolproof strategies. "I love my wine, but when I'm really trying to lose weight, that's got to go," she shares. "Alcohol is a trigger to make bad choices, just like when I get too hungry." And when it comes to snacks, she always finds different ways to get creative. "I do cool things with snacks. My favorite is a Wasa cracker topped with avocado, radish, chia seeds, a little olive oil, some sea salt, lemon, and dill," she says. "That keeps my palate excited."