Jalapeno Poppers

There are many ways to make them. I cut jalapeños in half lengthwise, remove all seeds and veins, stuff with cream cheese and half a little Smokey link, then wrap with half a strip of regular cut bacon. 
 Pro tip is to allow the bacon to warm up a bit so it is vastly more pliable. You can literally flatten it about a bit to increase cove age when wrapping. Once you have them wrapped put your tray back in the fridge and they with firm up and hold their shape. Don’t need a toothpick unless you want one for convenience of handling. I go sans toothpick. 
 I see people using pimento cheese amongst others in lieu of the cream cheese. Also different meats such as pulled pork or brisket under the bacon.  Your imagination is your limit. Good luck! 

ABT's as they are referred to around here.  You are only limited by your creativity.  I prep the jalas (wear gloves) as above, split length-wise and devein and remove the seeds.  After that the stuffing is all yours.  My favorite mix is chorizo (fully cooked first) tossed in a blender then mix in habanero cheese to create the filling.  Load the jala, wrap with half a slice of regular thickness bacon and away you go.
A great dessert version created by @henapple is to load with a piece of dark chocolate and a cherry then bacon wrap and cook.  MPD's (Mexican Panty Droppers).
You can use about anything for the mixture, sausage, pulled pork, brisket, shrimp, chix etc.  Cheese a matter of personal preference.  Experiment and have fun with 'em.  FWIW-

I just saw you said you needed to do them a few days in advance. I’m assuming you meant but them together, not cook? 

I wouldnt advise cooking them a hen a day or two before. The jalapeño won’t hold. Worst case you could just cook them in an oven on a wire rack. You will still have better quality than cooking ahead of time. 

I’ve had some with a butterflied shrimp nestled between the cream cheese and bacon. Man were they great.  A bit of scallion and DP in the CC makes it nice and tastie.