Cut dates in half lengthwise and remove pits. Spoon about 1/2 teaspoon cheese into the cavity of each date half. Arrange dates on a serving plate.
Melt butter in a 1- to 2-quart pan over low heat, then increase heat to medium and cook until butter is foamy and starting to brown. Add nuts and stir constantly for 1 minute. Add syrup and reduce heat to maintain a simmer. Cook 1 minute, stirring frequently. Remove from heat.
Lift nuts from the syrup with a slotted spoon and press a few pieces into the soft cheese in each date. Drizzle syrup over the dates and serve warm.