Melt 1 tbsp butter in a skillet over medium heat. Add the pecans and toast for 3 to 4 minutes, stirring often, until fragrant.
Sprinkle in 1 tbsp brown sugar and a pinch of salt and stir for 1 minute until the nuts look glossy. Spread them on parchment paper and let cool completely. In a small saucepan over medium heat, melt 4 tbsp butter and keep swirling the pan for 4 to 6 minutes. It will foam, then turn golden brown with toasty brown bits on the bottom and a nutty smell.
Remove the pan from the heat and whisk in the brown sugar, then carefully whisk in the milk, as it will bubble up. Return to low heat and whisk for 1 to 2 minutes until the sugar dissolves into a smooth butterscotch, then cool for 15 minutes.
Pour the butterscotch into a high-speed blender, scraping in all the brown bits. Add the cottage cheese, heavy cream, vanilla and salt and blend for 1 to 2 minutes until completely silky.
Transfer the base to a container and refrigerate for at least 2 hours until very cold.
Churn the base in a pre-frozen ice cream maker for 20 to 25 minutes until thick and creamy. Add the candied pecans during the last minute of churning.
Transfer to a freezer-safe container, press plastic wrap onto the surface and freeze for 3 to 4 hours until firm. Soften at room temperature for 10 minutes before scooping.