In food processor, pulse all dry ingredients with butter until it has the appearance of corn meal.

Add the flour mixture to a bowl and then add yogurt until the mixture sticks together without being too sticky - just until it holds together in one mound. If it needs more moisture, add some half and half to the mixture.

Once the mixture resembles dough, add the pureed squash and mix together.

Turn out onto floured surface, flatten out with hands to about a one inch thickness (you can use a rolling pin too). The thickness is important as the biscuits will rise taller and look fluffier.

Cut small rounds, place on baking sheet and brush tops with a little half and half.

Bake for about 7 minutes, or until nicely browned.