Nana's Butter Cookies with Milk-Jam Filling

Nana's Butter Cookies with Milk-Jam FillingEva Kolenko
The caramelized milk jam makes for a decadent little sandwich, but these cookies are amazingly good simply eaten on their own.
Do ahead:
Dough can be made 5 days ahead. Keep chilled. Milk jam can be made 1 week ahead. Cover and chill.

