My girlfriend got mad when i told her to never make me a sandwich.?!

Hi, so me any my girlfriend have been dating for three years now. My girlfriend is somewhat a feminist, but i love that about her because she isn't afraid to stand up for her beliefs. I admired women who are feminist. So i am pretty much a better cook then my wife, my wife isn't the best cook as you can see. My girlfriend does try to cook, but i do not like her cooking. I think my girlfriend notices i don't like her cooking, but i always tell her that the food is good. So I am the one who is cooking most of the foods in the house, it has been that way for a while now. I do my best to make sure she does not cook any food at all. I don't have a problem with cooking for her, and she doesn't mind also.

So one day while we were watching tv. My girlfriend said you never ask me to make a sandwich for you. It is because i always fix it myself. Then my girlfriend said she wouldn't mind fixing me a sandwich if i asked polity, since i cook all the time (I make better sandwiches then my girlfriend). Then i told my girlfriend to never fix me a sandwich ever because i love my sandwiches the best. I said that's one less thing you have to worry about, then i told her that i respect her and she is not my maid. Also, i added i can fix myself a sandwich if i wanted one. She then began to act weird, and started looking sad. Soon she said she was going to her room to write a poem. I got silent treatment from my girlfriend since it happened, it happened this morning

My girlfriend took what i said the wrong way. Now she thinks i hate her cooking, she thought i was cooking because i loved to. She views me as arrogant now. Now she views me differently, i didn't mean to get in this trouble. How can i get my girlfriend to understand i was being polite. How do i get our relationship back to normal again. I miss my girlfriend really badly.