Cold Stone to Matthew Stafford -- LET US PROVIDE WEDDING DESSERT ... For Free!!

Matthew Stafford could have an ice cream cake at his wedding ... 'cause Cold Stone is so pumped the QB announced his engagement at one of their shops, they're offering to provide ALL OF THE WEDDING DESSERTS for free!!

TMZ Sports spoke with Cold Stone head honcho Michael Serruya who tells us ... "We'd love to provide dessert for everyone at the wedding. And to the extent that they would allow us, we would love to make the cake as well!"

As we previously reported, Matt and longtime GF Kelly Hall posted the obligatory "check out the ring" pic while chowing down on ice cream at a Cold Stone earlier this week.