With Brankaresh and Eileen, I've deliberately not written one big argument scene, rather a series of hints that she has caught him out with bad magical practices. These hints of course lead on to his hints (and more!) that he resents her for this.
I've learned over time it really is best to drip feed information. It is very tempting to tell your readers all they want to know in one go (gets it out of the way, doesn't it?) but the story reads and flows much better if information is fed in gradually. It also means your readers can build up pictures for themselves as to what is going on and I know I love books that encourage me to do some work there.
Little details such as how a character speaks can add depth to your story. L'Evallier, Chief Elf, will never use a contraction in speech (yet alone in writing) and it confirms his very posh pedigree. It all fits together.
I try to think of information feeding as a case of putting it on with thin brush strokes, rather than laying it all one really thickly with a trowel!