'American Idol' Carrie Underwood on 'Ellen': 'So honored' to be in 'Idol Gives Back'

Carrie Underwood stopped by "The Ellen DeGeneres Show" to hand out two tickets to "Idol Gives Back" to an audience member.

Carrie shows off her ginormous yellow diamond engagement ring, but says that the wedding planning is going to be pretty laid back.

"We're trying to keep it as small as possible," she tells current "Idol" judge Ellen DeGeneres. "He's got so many family members and all my friends are people that I work with and I love to death, but we're trying to keep it as small as possible."

Carrie says of "Idol Gives Back," "This is my third year doing it and I just think it's so amazing. These huge television shows have such a public, social responsibility to use their power for good and I'm so honored that they let me come back every year and perform on the show."

Carrie also says that $.36 of every ticket sold for her "Play On" tour is going to Feed the Children. She chose the amount because it is quoted in a line from her song "Change" -- "What you're gonna do with the 36 cents/ Sticky with coke on your floorboard/ When a woman on the street is huddled in the cold/ On a sidewalk bench trying to keep warm" -- and it shows that a little donation can make a big difference.

It won't, in fact, end up as a little donation -- she is performing at nearly 100 venues, a conservative estimate at the average capacity per venue is 10,000 seats and most shows have been sold out. That works out to roughly a $360,000 donation.

Be sure to look for Carrie's performance on the Wednesday, April 21 "Idol Gives Back" special. Also check out the Top 7 Idols' thoughts about participating in the charity event and an Ellen DeGeneres sneak peak.