Toast the pine nuts in a dry skillet over medium-low heat for 3 to 4 minutes, stirring frequently until golden. Transfer them to a plate to cool.
Combine the allulose, heavy cream, butter, rosemary sprig, and sea salt in a small saucepan. Simmer for 4 to 5 minutes until lightly amber and slightly thickened.
Remove the rosemary caramel from the heat and discard the rosemary sprig. Refrigerate the caramel until completely cold.
Blend the heavy cream, almond milk, powdered allulose, cream cheese, vanilla extract, xanthan gum, and sea salt until smooth, then refrigerate for at least 3 hours.
Churn the ice cream mixture in an ice cream maker according to the manufacturer's directions. Add the toasted pine nuts during the final minute.
Layer the ice cream with thin ribbons of rosemary caramel in a freezer-safe container. Freeze for 3 to 4 hours before serving.