Seeded eighth at Roland Garros, Andreeva had dropped just a single set en route to the showpiece event, and the 19-year-old continued her imperious form on Saturday afternoon, ending the fairytale run of Chwalinska at the final hurdle.
Andreeva fired down 25 winners while converting seven of 12 break-point chances in a statement display, as she underlined her credentials as one of the world's best players, becoming the youngest woman to win a major since Emma Raducanu at the 2021 US Open.
"I've been watching Roland Garros on TV since I was very, very young, so it's also a big dream of mine to win this tournament and I honestly cannot believe that I'm holding this trophy right now," Andreeva said during the trophy ceremony.
"Congrats to Maja for these amazing three weeks, passing through qualies, winning so many matches, beating so many great players."
Both Chwalinska and Andreeva struggled on serve in the early exchanges, with four successive breaks to open the match, as the two players settled into a rhythm on Philippe-Chatrier.
However, it was the 19-year-old who soon took control of proceedings, as she broke Chwalinska for the third time in the seventh game, before putting her foot on the accelerator to capture the first set in 43 minutes.
From that point, it was one-way traffic, with Andreeva using her superior firepower from the back of the court to overwhelm her Polish opponent.
The Russian continued to rise to the occasion as the second set progressed, and despite a brief wobble when serving for the title, converted her first match point to secure the biggest victory of her burgeoning career.
Defeat brought an end to Chwalinska's astonishing run in Paris, which started in qualifying, as she won nine matches in a row to become the first qualifier to reach the final in the Open era.
"Congratulations to Mirra, such an incredible player, so young and so talented, it's so annoying. Congratulations to your team as well, for an amazing job, and all the best for the future," said the Pole after the match.
"I wish we could see a better match today, but Mirra is too good, so I guess it's her fault. I tried my best. I'm sorry. I will never forget these three weeks, Paris will forever be in my heart."