That's a take on the classic South American dessert Romeo y Julieta, us. a fresh white cheese and quince. Quince paste is ubiquitous, particularly this time of year. It's called pasta de membrillo in Spanish. El Mercado, the Argentine bodega on Southport has a good selection. Get one in a tin, as opposed to cellophane. I'd consider using a mix of good mozzarella (a tangy buffalo mozz might work well here; search for info) and queso blanco, a basic white fresh cheese like a firm ricotta, also at Mercado. Somewhat bafflingly, Costco carries massive blocks of queso blanco from a good manufacturer, Caribe, from time to time as well. You could warm up the quince paste and spread it on like a "sauce" if you want.