You could perhaps take some ideas from vegetarian recipes. Obviously, I know chicken isn't vegetarian, but if you need to avoid bacon there are vegetarian options for imparting the flavouring that you would otherwise get from bacon.
If it's a smoky flavour I want, I use Spanish smoked paprika. I frequently use it in lentil soup when cooking for vegetarian friends to avoid using bacon/ham. I use it in combination with vegetable stock cubes. Another smoky-flavoured spice is chipotle chili flakes - obviously this is much spicier than paprika, so be careful!
Another possibility is to use something like dried mushrooms, such as porcini; these have an almost pork-like concentrated umami/savoury flavour. I've also seen porcini mushroom powder, which can be used similarly, if you want to avoid pieces of mushroom.
Perhaps you could use a combination of all of these.
Another option, not vegetarian, is what is often referred to as Italian MSG - salted anchovy fillets. I know it sounds a bit weird, but these can add a wonderful salty meaty/umami flavour to dishes. Maybe just use two or three fillets. They will dissolve almost completely in a sauce. They're a strong flavouring but in small quantities they don't add a fishy flavour at all.