The 41-year-old mogul was joined by husband Jason Hoppy, 40, and daughter Bryn, 21 months.
The pair will celebrate their second wedding anniversary on March 28. In 2012, they tied the knot during a lavish ceremony on the first season of her Bravo show, then called Bethenny Getting Married?. Byrn was born a little over a month later.
In addition to revealing her flat abs and impressive cleavage on the beach, the Bethenny Ever After star flashed her mega engagement ring, which looks more dazzling than usual thanks to Hoppy, who recently updated the sparkler.
PHOTOS: More gorgeous celebrity engagement rings"When we got engaged, my jeweler Kristen Farrell found us a great deal on an engagement ring that someone was selling," the former Real Housewives of New York star told Us Weekly of the multi-stone bauble, which now features one giant stone. "We had wanted a certain setting but couldn't afford it, so we waited until we could design our ring the way we wanted.