Sounds like a toddler & infact they like to eat the same thing time & time again, they like the consistencey of it & it makes them feel safe.
I offer the same thing to both mine day in day out, but add a different (new) thing as well to see if they will try it... I offer the same new things every second day for about 2 weeks then if it hasn't been tried stop & move on.
Toddlers are "supposed" to be picky eaters & if you look at what they eat over a week (& you offer healthy balanced choices) they actually do eat a balanced diet.
I don't think you should try to get her to eat more variety or quantity, but accept that she is choosing what she wants to eat.
Trust me we went through a point where my ds#1 ate less than 10 different foods, but they included meat, cereal, fruit & veg + dairy so I just accepted it (he was eating from each food group) as in a week he ate 7-10 apples (often 3-4 in one day) etc ... I was the same as a child & eat nearly everything now