1) Preheat oven to 100 degrees C/Gas Mark 1/4.
2) Defrost spinach 10 minutes on defrost setting in microwave then drain well by wringing out in dish towel. Defrost artichokes as well, 6 minutes on defrost in microwave then wring out and finely chop.
3) Heat a saucepan with butter over medium to medium-high heat. Add garlic to melted butter and stir 1 to 2 minutes, then sprinkle in flour and combine 1 minute more. Whisk in stock and milk and season with salt, pepper and nutmeg. Thicken 2 minutes then remove from heat and melt in gorgonzola.
4) Stir in spinach and artichokes and half the shredded cheese then transfer to a small casserole dish and top with remaining cheese.
5) Brown and bubble in the oven for 10 to 12 minutes.
6) Serve with bread sticks, celery hearts and pita crisps for dipping.