Hello MidwestJess. When it comes to baking with high calcium foods that are not milk or spinach, you have several wonderful options that integrate seamlessly into recipes.
Chia seeds are an exceptional choice because they are rich in calcium and can be ground into a powder or used whole in breads, muffins, and cookies without altering the texture too drastically. Sesame seeds or tahini paste are also fantastic; tahini can easily replace a portion of the butter or oil in cookie and cake recipes while boosting calcium significantly.
Almond flour, made from whole almonds, provides a good amount of calcium as well and works wonderfully as a base for gluten-free baking. Finally, calcium-set tofu can be incorporated into certain quick breads or vegan baked goods. I hope this helps you create some healthy and nutritious treats!