08/15/2008 AT 01:05 PM EDT
When Desperate Housewives
' Felicity Huffman made her Broadway debut in David Mamet's Speed-the-Plow
in 1988, she made an interesting discovery in her dressing room: A thong belonging to Madonna
"I was like, 'This is Madonna's underwear," she tells More
Magazine in its September issue.
So what did she do? She promptly tried it on! "Of course, it didn't fit me," she says.
During a wide-ranging interview, Huffman also tells the magazine about her personal life helping her audition as Desperate Housewives
' most harried mother.
"I'd just left two screaming kids in the bathtub and it was raining," she recalls. "I thought I pulled myself together well. Later on, one of the producers said, 'It was so great, because you were such a mess and so frazzled, and your pants were filthy.' "
On becoming a household name after 40, the actress says, "If this success had happened when I was younger, I would have been too tortured to appreciate it. Now that I'm older, I can go, 'God, this is fantastic!' "
Huffman also thinks her 11-year marriage to actor William H. Macy is fantastic: "Every time Bill Macy walks into the room, my heart still jumps. That is true to this day."
MORE: Check out PEOPLE's tribute to Madonna, who turns 50 Aug. 16