Am I the Asshole for cooking food while my roommate's girlfriend was here & offering her some

I(21m) am from the south. I grew up in New Orleans and Texas. My mom runs a catering business and the majority of clients were either at home in Louisiana or in Texas. I add this to say that I grew up cooking and helping my mom cook for the business. I was frying chicken and catfish when I could reach the stove and making gumbo and buttermilk biscuits at a very young. I'm currently in culinary school right now.

I've lived in a rented house on the east coast with my roommate(22m) for a year and a half. He's not a friend or anything. We just linked up because we both needed roommates in the area. He's good to live with and we watch shows and movies together. We hang out and go out for drinks sometimes. I always make friends easy because of being from the south and doing customer service related things since I was a kid. I know how to talk and charm and listen to folk despite being naturally more in the introverted spectrum. My roommate has been seeing his girlfriend(20m) for like 6 months. I've met her before and seen her in passing. Roommate and his gf had a 2 week break from school things. She still lives at her parents so she decided to stay here the whole two weeks. I was just doing things as I would normally do. It got weird at first when I was about to go mow the lawn and the roommate stopped me and said he wanted to mow(I usually always mow.) A couple of days later I was outside washing my car. I asked both of them if they wanted me to do theirs. She looked like she was going to agree but he looked at her angrily so they declined.

I cook pretty frequently at home as well and usually let my roommate have some. So any time I'd make some I would say that they could have some and this would get him pissed. Weeks prior when she was here and we were all talking. She mentioned this specific kind of cheesecake that she really likes. So I made and sent out a group text that everyone could have it. My roommate got upset. I don't see anything as overstepping a boundary as this is how I treat him and all guests. The other day he told me how annoying it was to hear his gf talk about "how good your roommate can fresh baked bread is." I'm not trying to make him look bad or anything. This is simply how i was raised. If I bake two loaves of bread I'm gonna leave it out for the house to eat.

EDIT- The cheesecake is just common courtesy type thing to me. When his parents come over i make pound cake because they like it. If a guest is coming you get/make what they like. Nothing odd about picking up their favorite chips or making some tea when guests arrive. Just how I was raised

EDIT- Wow this has blown up. Just want to say we generally have a good roommate relationship. We're not best friends but it's friendly enough. The only change has been when his gf is here. So lol no I am not looking to for new roommates/to be adopted/or to move but thanks. Here is some more things that upset him.

I went to the grocery store and asked if anyone needed anything

I was frying chicken and offered the first/best pieces out the oil to them

I changed the oil to my own car

I used a smoker in the backyard to make brisket

I grill and smoke in the backyard and needed a piece of wood cut into a certain way to hold something up. I cut and nailed some wood together in the garage.

Feels like I can't even exist while she is here

FINAL EDIT- I tend to see the good and best in people. So I was not seeing him as being very insecure and was trying to look at this in a more positive light. But he just texted me and said that I greet his gf in too kind of a way and it's annoying that I say "be safe" when she leaves the house(I say this to him and everyone when they they tell me they are going somewhere). He sent me a long text detailing it's bad that I look her in the eyes when she is talking to me??? Maybe it is time for a new roommate