The British singer reportedly spilled the beans during her Friday Las Vegas show ... telling the crowd once her residency wraps up, she's putting baby-making on the top of her to-do list with Rich Paul -- and she's totally hoping for a pink gender reveal.

Adele said she wants a girl 'cause she's ready to balance out her squad. Remember, she was previously married to Simon Konecki, and together they share their son Angelo, who's now 11.

Speaking hypothetically about having a mini-me girl, Adele noted, "I feel like she might be like the person I love the most in the world, but also probably hate the most in the world. That is what I feel will happen. She's going to put me in my place all the time, isn't she?"

Adele's painted quite the picture ... saying with Rich's head-strong personality and her own sassiness, their daughter would be a bossy little queen!

Luckily, Adele's been getting some practice in the girl-mom department since being with RP, thanks to his daughter Reonna ... who she gave a shout-out for her graduation, telling her, "I love you, darling."

If you're familiar with Adele, you'll know getting a glimpse into her relationship with Rich is super rare ... as the two of them are very private.

Frankly, we're still not even sure if the pair are actually married after Adele sported an enormous rock on her ring finger during a courtside appearance with RP last November -- and to add fuel to the fire, Adele even referred to herself as RP's wife in the past.