An elderly relative has the same physical symptoms as many stroke victims: weakness on the right side, curled/stiff fingers, and some difficulty in swallowing on the affected side. He loves cornflakes with milk. My husband thinks a thickening agent should be added to the milk to preclude occasional choking spells. However, the old gentleman can manage potato chips, raw vegetables, pills, etc. without rarely any difficulty.
What kind of thickening agent is available? Does it have a taste?
Would it ruin the enjoyment of the bowl of cereal?
I used this to thicken liquids for mom after a stroke. You didn't mention how recent the stroke was. Have you asked your dr for a speech therapy consult? They don't just work on speech - they work to help people with swallowing difficulties. If too much time hasn't passed, they can do electrostimulation on throat muscles to help with the recovery, and also can teach some techniques to assist with swallowing.
Good luck.