1. Purée raspberries with 3 Tbsp water in a food processor until smooth. Strain purée through a fine-mesh sieve, pressing on solids to release as much liquid as possible. Discard solids. Stir sugar and lemon juice into raspberry liquid.
2. Melt butter with brown sugar in a skillet over medium. Brush butter mixture on peach halves. Grill on medium until tender, about 8 minutes, turning occasionally. Remove peaches from heat; allow to cool slightly and slice.
3. Arrange peaches in serving bowls and drizzle with sauce. Serve with shortbread cookies and a dollop of whipped cream, if desired.
Cook’s Note: The sauce can be made a day ahead of time; cover it and store in the refrigerator. Grill the peaches just before serving.
Serves 6. Per serving: 170 cal, 30g carbs, 2g protein, 7g fat, 15mg chol, 0mg sodium, 5g fiber TOTAL COST: $10.13