In a large pan, heat one tablespoon olive oil over medium heat.

Add the onion cubes and sauté until soft and translucent.

Add the garlic cubes and stir for another minute.

Stir in the kohlrabi sticks and cook for about three to five minutes, until softened.

Add the shredded carrots and frozen spinach, cooking for another five minutes, stirring occasionally.

Season with salt to taste, then remove from heat. Let cool.

Preheat the oven to 375 degrees Fahrenheit (190 degrees Celsius). Lightly grease a 12-cup muffin tin.

Lay out one sheet of phyllo dough and brush it lightly with melted butter.

Layer another phyllo sheet on top, butter it, and repeat until you have three layers.

Cut the stacked phyllo into 12 squares.

Press each square into a muffin cup, gently molding it to fit.

Repeat with the remaining three phyllo sheets to make another set of 12 layered squares, filling all 12 cups.

Bake for five minutes.

Remove from oven and add filling, dividing evenly. Bake another five minutes, then remove from oven and let cool.