Pineapple is great on the grill because it can caramelize and sear without falling apart, and its already sweet juices get even sweeter when subjected to heat.
Heat oven to 325°F. Line a rimmed baking sheet with parchment paper.2.
In a medium-sized, microwave-safe bowl (or saucepan), heat honey until it's runny, 20 seconds in the microwave or 1 minute on the stove.3.
Add nuts and sugar and stir well. Spread nuts out into an even layer on the prepared baking sheet and bake until golden, 15-18 minutes. Let cool, then break up into pieces.4.
Meanwhile, heat the grill or grill pan. Brush pineapple with oil, then grill, cut-side down, until grill marks appear, about 5 minutes. Brush tops with oil, then flip pineapple over and grill until marks appear on the other side, about 5 minutes longer.5.
Transfer to a serving platter and top with crème fraîche or sour cream and cashews. Sprinkle with cinnamon and serve.