If you are looking to up your fat and calories, there is no better way than olive oil. I just mix up my own salad dressing of 3 TBS olive oil, 2 tsp. vinegar, and a dash of Italian seasoning. That's a delicious 41 fat grams that is essentially no-carb.

Other resources are mayonnaise (I love it on broccoli and asparagus) and heavy cream.