In a small saucepan, bring water, sugar, thyme and rosemary to a boil. Simmer until sugar is dissolved and the liquid is reduced to 1/2 cup. Strain and cool.
2
Peel and core 2 or 3 ripe pears and process them with the lemon juice in a food processor or blender.
3
Add the herb simple syrup and process until combined.
4
Process in an ice cream machine according to manufacturer's instructions.