In a large bowl, whisk together the sweetened condensed milk and vanilla extract until well combined. Set this mixture aside.

In another large bowl, use a mixer to whisk the heavy cream on medium-high speed until firm peaks form, about 2 minutes.

Gently fold about half of the whipped cream into the bowl with the sweetened condensed milk using a spatula for a smooth combination.

Add the remaining whipped cream and mix gently until incorporated.

Drop large spoonfuls of the roasted blueberries on top of the mixture. Swirl them through the ice cream to your preference.

Pour the mixture into a chilled 9x5x3 metal loaf pan. Cover with tinfoil or a lid, and freeze until solid for at least 3-4 hours.