In a saucepan, combine the Thai tea mix, whole milk, and ½ cup of heavy whipping cream. Heat over medium-low until the mixture begins to steam, stirring occasionally.

Remove the saucepan from heat and let the mixture steep for about 15 minutes.

Strain the mixture through a fine mesh sieve into a bowl to remove the tea leaves.

Whisk in the sweetened condensed milk and vanilla until fully combined.

Chill the bowl and whisk attachment of a stand mixer in the freezer for about 15 minutes.

After chilling, whip the remaining 1 ½ cups of heavy cream on high speed until stiff peaks form.

Gently fold the whipped cream into the Thai tea mixture in two batches until just combined.

Transfer the mixture to a loaf pan or suitable container. Cover tightly and freeze for at least 6 hours or overnight.

In a pan, toast the coconut flakes over medium heat until golden brown, stirring frequently.

Serve the ice cream in bowls and garnish with toasted coconut flakes.