What about making a layered casserole, rather than everything mixed together? ... and I'd be tempted to leave out the mushrooms. Save those to fry in butter and tuck inside an omelet for tomorrow's breakfast/brunch .

First .. slice the sausages and brown them in a little oil. Spread in the bottom of your casserole/baking dish. In the same skillet, soften chopped onion, garlic and jalapenos (add more oil if needed). Meanwhile, drain the sauerkraut really well (to avoid a soupy, watery mess). Stir the onion-jalapeno mix into the kraut, plus a grind or three from a peppermill .. then spread this over the browned sausage slices. Top with cream cheese cubes (easier to do if the cream cheese is really cold and firm). Bake in preheated 400 F oven till bubbly and cheese is melted and golden brown. Maybe 15 minutes? The sausages and veg are already cooked so it's just a matter of browning the top. If you have some paprika or smoked paprika, would be nice to sprinkle on top before it goes into the oven.

Alternately, you could try blending the softened cream cheese with an egg, then spread over top of the sausage-kraut layers like a custardy topping. Bake as described above.