Use olive oil, butter, mayo and so on. On days I need to up my fat I'll suppliment with coconut oil. I'll actually just take a tablespoon full of the stuff. Many do this with flax oil or fish oil for heart health.
I also eat alot of veggies. I've learned to add butter or olive oil to them. It also helps the taste. Breaking my day up into many smaller meals also helps to raise my calorie levels.
I also have the chicken tenders. But what I do is use 4 cubed up in my salad. I'll often cook them in an LC sauce such as BBq or Teriyaki. Then I'll put a tablespoon of olive oil on as a dressing. The oil mixed with the meat taste and works great.
I don't use dairy really at all. If I do it's a small amount of cream cheese or cheese, never heavy cream.
Ideas for cheap higher fat meals with veggies
Zucchini hasbrowns with eggs, butter on top
2 egg omlette with 1/2 cup spinich and 1 tbsp mayo as filler
Spaghetti squash with garlic butter for a side
Quiches
And so on.
To save money shop bulk, then wrap and freeze the meat in individual portions. Look for meat and seafood that has been reduced in price becaus eit's close to the sell by date. Stretch meat out as much as possible by adding veggies and what have you as fillers. Buy eggs by the ton
Look over other members journals and fitday accounts as insperation and to get ideas. Stay away from the sweets, and also LC breads and other franken foods. They may just stall you anyway and aren't really good to add back in intil later stages of OWL anyway.