Several questions asked full-time RVers are, "What do you eat, hot dogs each night? How do you cook?" The answers are, "Anything we want. No and we cook the same as we would in a household kitchen." If you want to conserve propane and you are connected to power, use an electric skillet. It doesn't take much propane to cook a meal. We regularly use a small barbecue during the summer. Also, if we have power, I use my crockpot. One pot meals are easy to prepare and ready to eat when you are.
One of the hardest lessons I need to learn, is to purchase a week of groceries at a time. While living in a house, we tend to purchase groceries on sale and in quantity. It's convenient to have groceries on a pantry shelf. In the RV kitchen, the pantry shelf is small, so purchasing a week ahead is best. You don't want cans and bags everywhere because they don't fit in a cupboard. If you are lucky, you may have room to store in the RV basement. I do not have such space, so all grocery items store inside. If I would make a grocery list each week and stuck to the list, I would not have too much in the cupboards and my refrigerator and freezer would not be working so hard. After six years, I'm still working on smaller grocery purchases. :o) This is one of those suggestions that are "do as I say, not as I do."
I keep "heat-em-up" dinners on hand. Several times a week we don't follow our menu plan. We are either out later in the afternoon or forget to get items out of the freezer to thaw. At this point, it is nice to have heat-em-ups. We don't eat out as often as we thought we would.
Most RV refrigerators are not as large as a household fridge. Purchase smaller containers of items such as condiments, milk, jams. You need to replace more often, but you provide more room in the fridge
Purchase smaller packages of cupboard products such as sugar, white and brown, flour, cereals. Sometimes it helps to take inside packages out of boxes.
I have two types of coffee pots, electric and a percolator. While connected to power, I use the electric drip pot. When boondocking, I use the percolator. This pot can also be used over a campfire.
We carry several cast iron skillets and a dutch oven. We use them inside and out.
Most RVs do not have a dishwasher. I invest in good paper plates and plastic drinking cups. I do not enjoy washing dishes and these items cut the washing in half.
Once a month, I need to reorganize my cupboards. I discover there are kitchen items I have not used in some time. I pass these items on to my kids, friends or donate to Good Will.
I have a large Corning Ware cutting board next to the stove. Helps to keep the counter clean and I use the cutting board when preparing meals.