1(12-ounce) bagfrozen raspberries (frozen or thawed)
Preheat the oven to 225 degrees. Line two baking sheets with parchment paper.
Place egg whites and cream of tartar in the bowl of an electric mixer fitted with the whisk attachment. Beat on high until soft peaks start to form. Gradually add ¾ cup of sugar, about 2 tablespoons at a time. Continue to beat until the mixture forms stiff peaks but is not dry. Beat in the vanilla.
Using a pastry bag fitted with a ½-inch round tip, pipe strips about 3 inches long onto the prepared baking sheets. Pipe a dot at each corner so they resemble bones.
Bake for 1 hour, turn off the oven, and let sit for another hour. Remove from the oven and let cool completely on the pans.
While the bones are baking, make the blood and guts. Whisk the cornstarch with 3 tablespoons water in a small bowl. Combine the raspberries with ½ cup sugar and lemon juice in a saucepan. Bring to a boil over high heat. Stir in the cornstarch mixture and let boil for 1 minute. Remove from heat, place in a bowl and let cool. Refrigerate until thickened and cold, at least 1 hour.
To serve, gently peel the bones off the parchment paper and serve with the blood and guts sauce.