The 28-year-old yoga instructor stepped out in NYC Monday wearing a subdued black ensemble, oversize sunglasses and one very notable accessory: her super-size diamond engagement ring.
This will be Baldwin's second marriage (he was previously married to actress Kim Basinger) and Thomas' first.
So how did the 30 Rock star's 16-year-old daughter Ireland take the news that her dad was remarrying?
Extremely well. In fact, the teen was quick to congratulate her dad and future stepmom on their big news.
"Congratulations @AlecBaldwin [and] @hilariathomas on getting engaged! Love you guys" she tweeted, adding [jokingly, we assume], "I'm going to be a flower girl."
Thomas responded to the teen's first tweet: "love you mas xoxo"