I render off the necessary fat over low heat, then remove the bacon strips, increase the heat, and fry using the rendered fat. When nearly done, I return the bacon to the pan to crisp it before serving.
Of course, you could also just save the grease from one batch to use with the next, thereby ensuring you always have both fresh-cooked bacon and (reasonably-fresh) grease to use without having to produce the former before the latter.
It depends on where you live. Each country has different meat diseases and bacterium that you have to be careful about
Traditionally in many western countries most meats are relatively safe raw though poultry is often not. But the definition of safe is not universal. Fresh chicken may have some salmonella etc, but unless this is allowed to grow to large numbers of spore it will not be dangerous. There are some bacteria that are dangerous in even minute amounts, but these should be vary rare, and even the cleanest cook will probably still transfer them
So to answer question, when cooking meat (or anything for that matter), you have to consider the amount of food adhering to the utensil, and the time it is exposed to a temperature in which bacteria can grow etc
If there was a formulae it would be something like
food type (risk of bacteria) * temperature * time
In general ground meat has been processed but not overly preserved, so time starts becoming a factor. How long has it been in a warm environment? Bacon is heavily preserved and not a great bacteria home, so you have more time before it becomes a risk. I small smear of bacon juice on a fork is not going to create a dangerous level of bacteria in the 20 minutes it takes you to cook the dish. But I wouldn't risk it for Chicken (in my country due to campylobacter still being a problem)
In the home environment I give anything that has touched raw food a quick rinse under the tap (Which just happens to be collected rain water and therefore full of bird poo :-) ) and sometimes a mechanical scrub with the dishes brush before using it again in the cooking process
There are lots of old wives tales on kitchen cleanliness, but the end result is that bacteria needs water, food, and temperature to grow. If you remove most of these they can't multiple to dangerous levels
From my experience in food technology laboratories, the often overlooked problem is surface oil and fat. These trap water, food and bacteria (the perfect storm). Simple mechanical scrubbing will remove vast amounts of these for short term (period of cooking) cleanliness
This of course does not apply to food that must be cooked for non bacterial reasons, and food known to be unclean. Chicken again is typical of this, and I would hot water scrub everything used with raw or partially cooked chicken
Best Answer
When I make quiche (and for a while at an old restaurant I was baking them almost daily) to which I am going to be adding anything other than the actual custard and flavouring, I look for three things: will these other ingredients release a lot of water when cooked? Will these other ingredients release a lot of fat when cooked? Will the other ingredients be fully cooked (if desired) in the final product?
In the first instance, most vegetables will release a significant amount of water when cooking. This has two unpleasant side effects: first, it creates steam pockets around the vegetable, preventing the custard from adhering and leaving empty spaces. Second, the steam itself can mix into and loosen the custard, preventing it from setting properly. Neither of these, as Brown would say, are good eats. Of course some vegetables let off more water, e.g. tomatoes, than others.
Second, dealing with fats, we generally have meats. Many meats will release fats while cooking, a process known as rendering. Bacon is of course the fattiest of meats you are likely to use; sausage would be similar. The release of fats into the custard will have many of the same effects as the release of water. In addition, quiche is often served cold, and excess animal fats feel unpleasantly greasy in the mouth when cold; unpleasantly oily and greasy when hot. Cheeses are not, for reasons I do not fully understand, generally a problem when the release their fats into a quiche. That being said, I have never tried baking a quiche with very fatty liquid cheeses such as brie or camembert; cream cheese and the similarly textured soft goat cheeses present no problem at all.
Finally, we must consider whether the ingredient(s) will end up cooked in the final product. Custards set at quite low temperatures, so this is an important safety consideration when dealing with meats. It is less important for safety with vegetables, and becomes an issue mainly of texture; do you want your vegetables to be crisp and crunchy or soft and limpid?
For all of these reasons, I always cook meat before including it in a quiche, unless it is charcuterie which is relatively low in fats and is safe to eat without further preparation, such as prosciutto (but not, I'd point out, jamon Iberico, if cut traditionally by hand, as it so often includes so much glorious fat that just melts lusciously... I digress). And I almost always cook vegetables; tomatoes, spinach (and other leafy greens) are always fully cooked to remove as much water as possible. Other vegetables depend on what I feel like. I generally will only blanch broccoli long enough to set a vivid green colour, as I like the contrast of soft custard with the crunchy broccoli. Your tastes may vary, of course.
Short version:
Meat: always cook! render out excess fat!
Vegetables: always blanch at least! cook out excess water!