Cookware that definitely transfers heat better?

What am I doing wrong here? I'm no cook, but I can follow directions. I fix Suddenly Salad pasta mixes a couple times a month, and never have a problem with the ones that call for mayo in the mix, but the ones that call for vegetable oil usually fail; when I pour the oil and water into the seasoning mix, it immediately forms little beads or balls, some over 1/4" diameter, no matter how long you stir. They're very hard to crush with a spoon, and appear to be dry inside, as if the oil forms a shell around the powder mix. The oil generally stays separated, not mixing well at all. I don't think the manufacturer had in mind using a spoon to laboriously crush these dozens of hard balls. And yes, the pasta and oil are within date. Am I using the wrong kind of oil? The instructions just say "vegetable oil" so I've been using "Canola Oil" as it seems to be pretty popular on the shelves. To me, one oil is like any other. Any ideas?

A spaghetti sauce recipe calls for cheese roux concentrate. It's added to the saucepan plus one cup of water. Should I just follow a cheese roux recipe, not bother about it being concentrate, i.e. adding a cup of water. If I make my own cheese roux I'd need directions, especially what type of cheese to add for a spaghetti sauce? I'm a terrible cook. Make the roux recipe detailed and dummy proof!