Add butternut squash and beets to the sauce. Mix well using 2 large spoons, making sure vegetables are well-coated with sauce.
Cover and cook until vegetables are tender, about 30 minutes, stirring a few times.
Meanwhile, steam broccolini. To do so, place a vegetable steamer in a pot, add 1 to 2 inches of water, cover and bring to a boil over medium-high heat. Add broccolini, cover again, and steam until crisp-tender, about 10 to 15 minutes.
Once steamed, you may leave broccolini whole or cut into bite-size pieces for serving.
When squash is cooked, discard lemongrass and add broccolini. Check seasoning and adjust salt to taste.
Garnish with fresh cilantro and drizzle with extra lime juice before serving.
Recipe by A Squirrel in the Kitchen at https://asquirrelinthekitchen.com/red-curry-aip/