Place the raspberries, sugar, and 1/4 cup water in a small saucepan over medium heat. Bring to a boil, lower the heat, and simmer for 4 minutes. Pour the cooked raspberries, the jam, and the framboise into the bowl of a food processor fitted with the steel blade and process until smooth. Pour into a container and chill. The sauce can be refrigerated for up to one week.
If you can't find seedless raspberry jam, you can heat 12 ounces of raspberry jam with seeds over medium heat and strain it through a sieve. Be sure to use real jam, not a "fruit spread."