Held at sunset in front of just 50 guests, including Mandy's co-stars Milo Ventimiglia and Chrissy Metz, the Pearson matriarch tied the knot in a blush gown.
Mandy is said to have arranged "very boho" nuptials with "rugs on the floor surrounding the altar" and a selection of "beautiful" floral arrangements, according to E!.
An insider told E! of their special day: "It was an intimate backyard wedding at Mandy's home that started just after sundown on Sunday evening. There was a small group of family and friends that looked to be about 50 people."
After the couple exchanged their "I dos", they continued the celebrations at The Fig House, which is a private event space in the Highland Park neighborhood of Los Angeles.
Minka Kelly, Sterling K. Brown and even Mandy's former flame Wilmer Valderrama were also among the famous faces who turned out for the couple's big day.
Another insider told E! there was no formal dinner at the nuptials, but a "number of food stations around the venue, including meat, chicken, vegetarian, raw food, flat bread, cheese and charcuterie and more".
Guests could also treat themselves to "a whiskey station, lots of wine, and 12 different kinds of cake".
But just hours before the wedding, Mandy suffered a tragic loss after her beloved cat Madeline passed away. The actress revealed her rescue cat died "suddenly" on Saturday evening.
Mandy and Taylor met on Instagram back in July 2015, with the musician proposing in the summer of 2017 after two years of dating.
The actress was previously married to musician Ryan Adams, 44, for six years from 2009 to 2015.
Mandy filed for divorce in January 2015, with the couple describing the marital split as "respectful, amicable parting of ways".
Speaking ahead of her wedding, the Princess Diaries actress revealed she had no plans to wear a traditional white wedding dress because she'd already been married once.
"No judgement, but it's not for me. I think it'll be just as small with family and friends. No bridal magazines for me."
The actress also revealed plans to keep her wedding low-key, telling E!: "It's not going to be some lavish affair, it's maybe something that isn't going to require as much planning or at least that's what I'm telling myself."