Jam Thumbprint Cookies

Bahan-bahan (32 porsi)

• 1 cup unsalted butter (room temperature)
• 1 cup granulated sugar
• 3 large egg yolks (room temperature)
• 1 tablespoon vanilla extract
• 3 cups all-purpose flour
• ½ teaspoon salt
• ¾ cup seedless raspberry jam (see note)
• ½ cup powdered sugar
• 1 teaspoon light corn syrup
• ¼ teaspoon vanilla extract
• 1 -3 teaspoons milk (divided)