Preheat the oven to 250°F and line 2 large baking sheets with parchment paper. Place the popcorn into a very large mixing bowl and remove any unpopped kernels. Sprinkle the popcorn with salt and toss lightly to combine.

Combine the heavy cream and sweetened condensed milk in a small saucepan. Heat until steaming but not simmering, then remove from the heat. Stir in the Thai tea mix and let steep for 5–7 minutes. Strain the mixture through a fine mesh sieve, pressing gently to extract as much flavor as possible. Set aside.

Combine the butter, dark brown sugar, corn syrup, water, and salt in a heavy-bottom saucepan. Cook over medium heat, stirring only until everything is dissolved. Once the mixture begins boiling steadily, stop stirring and cook for 3–4 minutes until the caramel reaches 242–244°F or becomes glossy and slightly darkened.

Remove the saucepan briefly from the heat and slowly whisk in the Thai tea cream mixture carefully. Return to low heat for about 10 seconds until smooth, then remove from the heat completely. Stir in the vanilla extract, almond extract if using, and baking soda. The caramel should foam lightly.

Gradually pour the caramel over the popcorn while tossing continuously to coat evenly. Continue mixing until the popcorn is fully coated, then spread it onto the prepared baking sheets in thin even layers.

Bake for 25 minutes, stirring every 8–10 minutes to ensure even coating and crisp texture. The caramel should appear glossy but dry rather than sticky. Allow the popcorn to cool completely before breaking into clusters. The popcorn becomes crispier as it cools.