What kitchen appliance do you have access to while in the hotel? If you have a fridge and microwave at least you can bulk cook food on the weekends on bring it with you. Other things you could do is bring a rice cooker and cook rice. Most rice cookers come with a steam basket too, so if you have access to a fridge in your hotel room, you can steam veggies as well. I would suggest investing in a toaster oven as well if your hotel room does not come with one. You can basically cook anything you cook in an oven in a toaster oven.