March 14 marks Pi Day, a celebration of the mathematical constant pi, which relates a circle’s circumference to its diameter. The holiday is often celebrated with pie itself. There are many different kinds of pie — from savory pies like shepherd’s pie and pizza, to sweet pies like apple pie and key lime pie. Here are three pie recipes to make for pie day, ranging from beginner to advanced.

Chocolate Pudding Pie

Ingredients:

1 box Oreos

4 tbsp unsalted butter

3 cups milk

1 large box of instant chocolate pudding mix

Whipped cream or Cool Whip

Directions:

1. Blend 25 Oreos in a blender into a fine powder.

2. Melt 4 tablespoons of unsalted butter.

3. Mix melted butter with Oreo powder until it has a wet sand consistency.

4. Pour the Oreo and butter mixture into a 9-inch pie plate.

5. Use your hands to spread the crust evenly throughout the pie plate and up the sides.

5. Use the bottom of a drinking glass to press down the crust to even it out.

6. Refrigerate or freeze the pie plate for 10-20 minutes before filling.

7. Prepare large pudding mix (3 cups) as directed.

8. Pour pudding into the pie plate before it sets.

9. Refrigerate until set.

10. Serve with whipped cream or Cool Whip.

Pi Day Pizza

Ingredients:

2¼ cups warm water

1 tbsp active dry yeast

1 tbsp sugar

2 tbsp olive oil

1 tbsp salt

5 cups bread flour

1 can tomato puree

Salt, basil, oregano, red pepper flakes, garlic powder, onion powder, black pepper, sugar, olive oil

½ lb mozzarella cheese

Mini pepperoni

Directions:

1. Add 2¼ cups warm water, 1 tablespoon yeast and 1 tablespoon sugar to a large mixing bowl and let sit for a few minutes to ensure the yeast goes foamy.

3. Add 2 tablespoons olive oil, 1 tablespoon salt and 5 cups bread flour to the mixture.

4. Mix with a spoon until just combined.

5. Knead the dough and add flour as needed to achieve desired pizza dough consistency.

6. Stop kneading after at least 10 minutes and you should be able to see light pass through the dough when stretched without tearing.

8. Divide dough into 4 balls and smooth out each ball into a nice sphere.

9. Pour a small amount of olive oil into four medium bowls.

10. Dip each dough ball in their respective bowl and spread the oil around to evenly coat both the bowl and the ball.

11. Cover each bowl with press-and-seal and let dough balls rise in the fridge for 1-4 days.

12. Make the sauce by first emptying one 29 oz can of tomato puree into a small mixing bowl.

13. Then add roughly one tablespoon each of salt, basil, oregano, red pepper flakes, garlic powder, onion powder and black pepper.

14. Then add about two tablespoons each of sugar and olive oil to the sauce.

15. Mix the sauce with a spoon or whisk until homogenous.

16. Refrigerate or freeze the sauce until ready to use.

17. Preheat the oven to 450 degrees.

18. Shred or thinly slice ½ lb mozzarella cheese (for four pizzas).

19. Lightly flour the cutting board to prevent dough from sticking to it.

20. Roll out pizza dough using a rolling pin or shape it by hand to desired thickness.

21. Add sauce, cheese and use mini pepperoni to make a pi symbol on the pizza.

22. Bake for 15 minutes at 450 degrees, or until the crust is golden brown and the cheese is bubbling.

Key Lime Pie

Ingredients:

1 box of graham crackers

6 tbsp unsalted butter

Salt

Brown sugar

Cinnamon

4 limes

5 eggs

2 cans of sweetened condensed milk

Whipped cream

Directions:

1. Preheat oven to 350 degrees.

2. Use a blender to blend 175 grams of graham crackers into fine crumbs.

3. Melt 6 tablespoons of unsalted butter.

4. In a 9-inch pie plate, mix the graham crackers, unsalted butter, a pinch of salt, ¼ teaspoon cinnamon and 80 grams brown sugar to form a crust.

5. Use your hands to pat the crust into a pie shape, including the base and the sides.

6. Use the bottom of a drinking glass to pound the crust into an even thickness on the bottom and the corners.

7. Blind bake the crust for 10 minutes at 350 degrees.

8. Let the crust cool completely to room temperature.

9. Preheat the oven to 350 degrees.

10. Zest 3 limes.

11. Juice roughly 4 limes to get ¾ cup lime juice.

12. Whisk 5 egg yolks and 2 14 oz cans of sweetened condensed milk in a small mixing bowl.

13. Add the zest of 3 limes and ¾ cup lime juice to the bowl and whisk to homogenize.

14. Pour the custard into the cooled pie crust.

15. Bake the pie for 30 minutes at 350 degrees, it should have a tiny amount of wobble left when pulled out of the oven.

16. Serve with whipped cream.