A stuffed rubber toy is the cheapest enrichment there is. It turns ten minutes of licking and chewing into something a French Bulldog has to work at, which is exactly what you want before you leave the house, during crate time, or on a day too hot for a proper walk.

Below are more than twenty fillings, from one-ingredient lazy options to layered frozen ones. First, the safety rules that make the difference between a good idea and a vet bill.

Before you stuff anything

Never microwave a KONG. Older versions of this article suggested melting cheese or setting egg inside the toy in a microwave. Don’t. KONG’s own guidance is that the toys are top-rack dishwasher safe but that you should “skip the drying cycle as excess heat can damage the toy” (KONG). Heating rubber also creates hot spots in the filling that can scald a dog’s mouth. Where a recipe below wants the filling set firm, freeze it instead.

Check peanut butter for xylitol. Xylitol, sometimes labeled birch sugar, is toxic to dogs: it triggers a rapid insulin release that can cause hypoglycemia, seizures and liver failure, sometimes within 10 to 60 minutes (FDA). Read the label of every nut butter before it goes near a KONG, and call your vet immediately if your dog eats a product containing it.

Keep some foods out entirely:

  • Grapes and raisins, which can cause kidney failure (ASPCA) — worth remembering before stuffing any fruit loaf or trail mix
  • Onions and garlic, which can cause anemia (ASPCA; AKC)
  • Chocolate and macadamia nuts, both toxic (AKC)
  • Cooked bones, which splinter
  • Raw egg whites, which can cause biotin deficiency; eggs are safe for dogs fully cooked (AKC)

Go easy on the fat. Liver sausage, cheese and oily leftovers make a KONG irresistible and they’re also the classic trigger for pancreatitis: a single large helping of fatty food can be enough to set off an attack (AKC). Use rich ingredients as a smear, not a filling.

Count it as food, not extra. Treats should make up no more than about 10% of a dog’s daily calories (VCA Animal Hospitals). The simplest approach with a daily KONG is to fill it with part of your Frenchie’s normal meal rather than adding on top of it — particularly for a breed where a few extra pounds makes breathing and joints worse.

Get the size right and supervise. Pick a KONG your dog can chew but can’t fit entirely in their mouth, and size up if you’re between sizes (KONG). KONG toys are for supervised use, and a damaged toy should be thrown away rather than repaired.

The red Classic suits most adult Frenchies. Puppies under nine months do better with the softer puppy version, and a determined chewer may need the black KONG Extreme.

Single ingredients that work on their own

Sometimes you don’t need a recipe. Any of these can go in by itself:

  • your dog’s usual kibble, dampened so it packs
  • canned dog food
  • plain cooked chicken, beef or lamb
  • plain cooked vegetables: green beans, peas, carrot, zucchini
  • plain canned pumpkin, not pie filling
  • mashed banana
  • plain, unsweetened yogurt
  • low-fat cream cheese, as a thin smear
  • xylitol-free peanut butter, again as a smear
  • plain cooked rice

A note from experience: everything on this list went down well with Charlie except anything involving carrots, which he has always refused. Your Frenchie may be the opposite.

Quick fillings

The five-second smear

Spread a spoonful of xylitol-free peanut butter around the inside of the large opening. The smell keeps a dog working long after the last of it is gone.

Kibble and water

Fill with kibble, add a splash of water or unsalted broth, and let it soak so the pieces bind together.

Kibble with a plug

Pack the KONG with dry kibble, then wedge a larger biscuit or a piece of carrot into the opening so it has to be worked loose.

Banana mash

Mash an overripe banana, mix it through kibble, and fill.

Yogurt

Plain unsweetened yogurt straight in, on its own or over kibble.

Pumpkin

Plain canned pumpkin, alone or mixed with kibble. Useful if your dog’s stomach is a little unsettled.

Cottage cheese and vegetables

A spoon of low-fat cottage cheese mixed with cooked peas or green beans.

Layered fillings

The trick is to make the first mouthful easy and the rest progressively harder.

Classic three-layer

Plug the small hole with a piece of kibble, add a layer of peanut butter, then kibble, then a final smear across the opening.

Meat and rice

Plain cooked rice mixed with shredded chicken, pressed in firmly.

Dinner KONG

Your dog’s measured dinner, dampened, packed tight, with a smear of yogurt sealing the top.

Fruit KONG

Chopped apple with no seeds, blueberries and a little mashed banana to hold it together.

Veggie KONG

Cooked green beans, peas and a spoon of pumpkin.

Bread and broth

A small piece of plain bread soaked in unsalted broth, folded in. No raisin bread, ever.

Tripe

Plain, unseasoned tripe from the freezer, thawed slightly, packed in. Strong-smelling and very popular.

Egg and kibble

Scrambled or hard-boiled egg, cooled and chopped, mixed through kibble. Cooked, never raw.

Frozen fillings

Freezing turns a ten-minute toy into a forty-minute one. Freeze a stuffed KONG for four to six hours, and stand it upright in a mug while it sets.

Frozen dinner

Pack the KONG with dampened kibble and freeze it solid.

Yogurt pop

Fill with plain yogurt and freeze. Mix in a few blueberries or banana slices first if you like.

Broth block

Plug the small hole, fill with unsalted broth, and freeze.

Pumpkin swirl

Layer pumpkin and yogurt, then freeze.

Peanut butter and banana

Mash them together, fill, freeze. The one most dogs would vote for.

Puppy porridge

Soaked puppy kibble blended with a little water, then frozen. Gentle on a teething puppy.

Chicken and vegetable

Shredded chicken and cooked vegetables in broth, frozen.

One caution with frozen KONGs: run it under the tap for a second before handing it over, so a tongue can’t stick to the cold rubber. And give frozen ones outdoors or on a washable mat, because they drip as they thaw.

Cleaning up afterwards

Rinse with warm water and dish soap, using a bottle brush or old toothbrush to get inside, and rinse thoroughly. For a KONG that’s been sitting, soak it first. All KONG rubber toys are top-rack dishwasher safe — but skip the heated drying cycle (KONG).

A red KONG toy standing on the top rack of a dishwasher

Having two or three in rotation is the practical answer: one with the dog, one in the freezer, one in the dishwasher.

A few Frenchie-specific notes

  • Watch the calories. French Bulldogs put weight on easily, and extra weight worsens the breathing problems the breed is prone to. Our guide to French Bulldog food covers portions.
  • Use it for crate time. A stuffed KONG is one of the best ways to make a crate somewhere your dog wants to be. See our crate training guide.
  • Mind the heat. A frozen KONG is a genuinely useful way to occupy a Frenchie on a day that’s too warm for a walk.
  • New foods, small amounts. Introduce one ingredient at a time, especially with a dog who has a sensitive stomach or food allergies. The Happy French Bulldog article on peanut butter for French Bulldogs goes into that one in more detail.

Stuff it, freeze it, hand it over, and enjoy the quiet.