'Doubling Down With the Derricos' Family Prepares Thanksgiving Dinner for 18 People in Finale Exclusive Sneak Peek

'Doubling Down With the Derricos' airs its season finale Tuesday, Aug. 8 at 10 p.m. ET on TLC.

It's Thanksgiving time at the Derrico household and the pressure is on to feed a delicious holiday dinner to a family of 18. Doubling Down With the Derricos dad Deon Derrico runs a tight ship in a PopCulture.com exclusive sneak peek of Tuesday's season finale of the TLC show, taking his eldest four kids to the grocery store for an impressive shopping trip that's sure to rack up a hefty bill. 

"Just know, this is not a normal dinner. This is Thanksgiving dinner for a family of 18," Deon explains to the camera as he goes over his lengthy grocery list with 11-year-old twins Dallas and Denver, 12-year-old son Derrick and 16-year-old daughter Darian. "It could easily be 10 dishes, whereas my regular family meals, it may be three or four. .. That's why my older four children are going with me to assist in getting all this stuff."

Giving a pep talk to the kids before kicking off the shopping spree, Deon goes down the list of must-haves, from collard greens and onions to turkey, eggs, chicken, and more. It's a very specific list, of which his kids are well-aware. "Poppy's OCD affects his shopping," Denver tells the camera in a confessional. "Poppy's really in particular about [the] type of brands he uses." Dallas agrees, "Poppy's OCD will be flaring up. ...Poppy will be all over the place."

Even Derrick agrees as his dad directs the kids to grab yams, bacon and six gallons of milk. "Poppy's OCD is on another level when he shops," the pre-teen admits. "He gets specific about what he buys." Derrick's job is grabbing eight regular pie crusts and bacon, but he's told to return the first slab of bacon he gets, as it's not the right brand. Darian confesses to the camera of her father, "He's very specific about getting, like, a certain brand of something. We don't go off-brand. ...And with Poppy's Derrico OCD, he's never gonna change that."

The Thanksgiving menu certainly will be extensive this year, with Deon grabbing 30 pounds of butter and two turkeys to deep fry for the family as well. "Every year, my children are getting bigger, and that means the meals are getting bigger also," he explains of the full cart. "I mean, they can put away some food."

The amount of food the Derricos are buying is certainly catching the attention of other shoppers, with Darian worrying, "Look at all this food. People are gonna think that we're greedy and we have a big family." Her dad reminds the teen, "We do have a big family," as they head to the check-out to total the damage they've done.

"Let's take these bets and [guess] actually how much this is gonna cost," Darian tells her siblings, submitting her guess of $300. The boys offer up their own guesses of $250 and $231, but right before Deon can read off the grand total, the clip comes to an end, leaving fans to wonder just how much the Thanksgiving grocery bill actually is. Doubling Down With the Derricos airs Tuesdays at 10 p.m. ET on TLC.