What do the twins bring for the painter and how does she respond?

In the story, the Morris twins bring dinner for the painter, but she responds without much enthusiasm for their act of kindness. In fact, she initially ignores the twins standing by with a jug of lemonade and a plate filled with cornbread, baked ham, candied yams, and collard greens.
It is only when Side Pocket speaks that the painter pauses her work and addresses the twins. She tells them that she has brought her own dinner and asks them to thank their mother on her behalf. The painter makes no effort to take the plate of food or the jug of lemonade from the twins. Meanwhile, the narrator is upset that the painter has acted so rudely.
Later, the painter visits the diner where the narrator's mother works. She seems to be very particular about not eating meat, particularly pork. The general impression the painter gives is not a positive one.

...she was asking Mama was that a ham hock in the greens, and was that a neck bone in the pole beans, and were there any vegetables cooked without meat, especially pork. “I don’t care who your spiritual leader is,” Mama said in that way of hers. “If you eat in the community, sistuh, you gonna eat pig by-and-by, one way or t’other.”

However, everyone soon discovers what the painter has been doing, and this changes their perception of her. On the wall, she has painted the images of Martin Luther King, Malcolm X, and Harriet Tubman (all heroes of the abolitionist or Civil Rights movement). She has also painted the liberation flags of Tanzania, Ghana, Guinea-Bassau, Angola, and Mozambique as well as images of the children who have hovered over her as she worked. Last, but not least, there is also an inscription dedicating the paintings to the people of Taliaferro Street.