My mom's apple cake

Ever since I was a little girl, my mom made an apple cake. This time around I changed the recipe slightly to make apple cake muffins with orange zest and cranberries. I baked them for 30 minutes. The original recipe is below:

Ingredients

3 eggs
1 cup sugar
1 cup flour
1/2 tsp baking soda
1 tsp white vinegar
1 tbsp sour cream or 1 tbsp oil
2-3 large granny smith apples

Optional : dried cranberries, raisins, vanilla, lemon zest

Directions

1. Preheat the oven to 375.
2. In a large bowl beat 3 eggs.
3. Add 1 c of sugar to the egg mixture and blend together.
4. Pour 1/2 teaspoon of baking soda into white vinegar - the two ingredients will react and bubble - add to the bowl with eggs and sugar and mix.

5. Slowly incorporate the flour into the above mixture.
6. Add either 1 tablespoon of sour cream or oil to the dough and set aside.
Note: if using any of the optional ingredients, mix them into the dough at this point.
7. Core and cube 3 large apples.
Optional: feel free to peel the apples if you wish
8. Butter a bundt pan or a glass dish.
9. Pour a portion or the dough until it covers the bottom of the baking dish.

10. Put the apples in and cover with the rest of the dough.

11. Bake in the oven for 45 minutes to an hour, until the top is golden brown and the toothpick comes out clean and dry.
12. Let the cake cool, and flip on a serving plate (if baking in a bundt pan).