Sure, a common use of bread, potatoes, cabbage/other vegetables, hearty meat dishes etc but the Polish kitchen is closer to Ukrainian/Russian in technique/ingredients.

Barszcz, pierogi, fermented everything, pickles, sour rye, and many dishes built around wheat/rye, mushrooms, dairy, and Eastern-style fillings are much more like Ukrainian/Belarusian/Russian food.

The biggest German influences are probably the sausages and the beer culture.